Method and apparatus for controlling an implantable medical device

ABSTRACT

A system and methods of maintaining communication with a medical device for exchange of information, instructions, and programs, in a highly reliable manner. Apparatus and methods for accomplishing this task include:
         1) The inclusion of a locating device in the system, in close proximity to an implanted device, but which does not drain the implanted device battery. The locating device may be implanted or external to the body.   2) The use of motion detection and global positioning system devices to locate elements within a communicating system for the medical device;   3) The assessment of received signal quality by elements of the system;   4) The use of a notification system for a device user who is moving out of range of communications; and   5) Documenting the absolute and functional integrity of instructions received by the medical device.

CROSS-REFERENCE TO RELATED APPLICATIONS

The subject matter of this application is related to that of:

1) U.S. patent application Ser. No. 10/460,458, published on Dec. 18,2003 as U.S. Patent Publication No. US/2003/0233129, now U.S. Pat. No.7,277,752;

2) U.S. patent application Ser. No. 11/502,484, published on Feb. 2,2007 as U.S. Patent Publication No. US/2007/0043585A1;

3) U.S. patent application Ser. No. 11/893,897, published on Dec. 27,2007 as U.S. Patent Publication No. US/2007/0299473;

4) U.S. patent application Ser. No. 11/895,934, published on Mar. 6,2008 as U.S. Patent Publication No. US/2008/0058884;

5) U.S. patent application Ser. No. 12/154,079, published on Dec. 4,2008 as U.S. Patent Publication No. US/2008/0300659;

6) U.S. patent application Ser. No. 12/455,940, published on Nov. 5,2009 as U.S. Patent Publication No. US/2009/0276013; and

7) Provisional Application No. 61/204,957, filed Jan. 13, 2009, priorityof which is hereby claimed.

-   -   The aforementioned U.S. Patent and published Patent Applications        are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Implantable medical devices (“IMDs”) exhibit growth in terms of:

a) the development of new devices which perform functions not previouslyperformed;

b) the development of more sophisticated devices that replace previoussimpler models; and

c) the number of implanted units per unit time.

Some devices perform “mission critical” functions—i.e. they stimulateheart, or brain, or deliver powerful drugs.

The devices are designed to function largely autonomously. That is, theyinteract with the patient in whom they are implanted (“the IMD owner”),and interact with an MD only on the infrequent occasions when the MD ispresent.

From time to time, the actions of these devices may result in unintendedand/or harmful consequences due to:

-   -   a) improper or suboptimal programming of the device by a        physician or technician;    -   b) a change in the condition of a patient, such that what was        appropriate programming in the past, is no longer appropriate        given the patients altered medical condition;    -   c) malfunction of the device itself;    -   d) malfunction of a sensor which provides information to the        device; and    -   e) electromagnetic interference.

Under these circumstances, it is desirable to have a means of veryrapidly addressing a malfunction or pseudo-malfunction [e.g. suboptimalprogramming], e.g. by reprogramming the device so that in the shortterm, one or more undesirable actions are prevented. Though the patientmay go to a physician's office or seek help in an Emergency Room, theseactions may require hours to days to execute. On the other hand, theability to remotely communicate with an implantable device, and tocontrol its function remotely, can provide a solution that is availablein minutes or seconds, and can provide real-time corrections as well.

The present application addresses various aspects of the communicationsbetween an IMD and a remotely located medical professional. Whereas thepreferred embodiment of the invention is an IMD, the inventive conceptsdescribed herein may be applied to other devices—medical andnon-medical—as well.

Abbreviations and Definitions

Adjacent—two communication units which may communicate directly

Alpha Unit—a communications unit which is upstream from a beta unit

Beta Unit—a communications unit which is downstream from an alpha unit

CCSI—composite communication status information

CPD—cell phone device

CS—central station

Downstream—refers to a communications unit which is linked to the IMD byfewer hops than a corresponding upstream unit. The upstream unit relaysa signal originating in the CS to the downstream unit.

EID—external RFID device

GPS—global positioning system

ICD—implantable cardioverter-defibrillator

IID—implantable RFID device

IMD—implantable medical device

IMD owner—the person in whom an IMD is implanted

MD/A/P—motion detecting accelerometer/piezoelectric crystal

MDC—motion detecting capability

PM—Pacemaker

Quiescent—a state in which mobile communicating units are not moving

RFID—radiofrequency identification device

SU—stationary unit

“Transmitting” may mean (a) as an RF signal, (b) over the telephonesystem, (c) via modem to the internet or (d) over a private carrier

Upstream—refers to a communications unit which is linked to the centralstation by fewer hops than a corresponding downstream unit. The upstreamunit relays a signal originating in the CS to the downstream unit.

WD—wrist device

SUMMARY OF THE INVENTION

Among the complexities of remotely controlling an IMD are the need forextremely reliable communications with the IMD, the need to notexcessively drain the battery of the IMD, and the need forcommunications security. To accomplish these goals, one must create anenvironment in which the IMD owner is, at all times (or as close to ‘alltimes’ as possible) near one or more communications repeater units.Ideally, at least one of the units would be either (a) very near the IMDowner, (b) carried by the IMD owner (e.g. a cell phone device, asdiscussed hereinbelow), (c) touching the IMD owner's body (e.g. a wristdevice, as discussed hereinbelow), (d) worn by the IMD owner or evenimplanted in the IMD owner. Redundancy among these communication unitsincreases the reliability of the system. By designating one or more ofthe units as a locator unit, i.e. a unit which is very likely to be inthe same location as the IMD owner at virtually all times, thecommunication system may be optimized on a frequent basis withoutdraining the IMD battery; i.e. optimization then involves elements ofthe system communicating with the locator unit, rather than with theIMD. By creating a system in which one repeater unit is very near theIMD owner, then at such times that communication with the IMD isnecessary, IMD power output can be low, and thus IMD battery drain canbe similarly low.

In the event that the system finds itself incapable of establishing arobust communications link between the IMD owner and a central station,then a means of notifying one or more individuals who can rectify thesituation is desirable. The notified individual could be the IMD owner,a person living or working with or near the IMD owner, or a systemadministrator who handles the task of seeking out the IMD owner.Notification may be via one or more of the devices in the IMD owner'senvironment which also serve as a repeater unit, e.g. the WD or the CPD.Among the short term remedies for the IMD owner are (a) movement to amore optimal location, (b) recharge or replace the battery of a repeaterunit whose battery has depleted, or (c) no action. The longer termoptions may entail an alteration in the environment, e.g. placing a morepowerful stationary unit in a location frequented by the IMD owner whichrepeatedly poses a communications challenge (e.g. his basement).

IMD communication networks are possible which are:

-   -   (a) self organizing—i.e. each repeater unit optimizes        communications with two or more neighbors;    -   (b) globally organized—i.e. a single unit optimizes the entire        system of communicating units; or    -   (c) locally organized—i.e. two or more units each optimize        communications among a local group (e.g. the CPD optimizes        communications in the environment of the IMD and another        upstream organizing unit optimizes communications at a point        between the CPD and the CS.

Devices that have been referred to as “cell phones” now are increasinglysophisticated, with substantial and increasing bandwidth access, memory,computational and advanced communication features. Such devices,suitably modified from a commercial off-the-shelf version, or a versionwhich is initially designed for an IMD owner, could function as arepeater unit, a notification unit and a local or global communicationsystem manager. Although such a unit could also be designated as theunit closest to the IMD-owner, a wearable or implantable device might dobetter.

Besides communications management, sophisticated information managementtechniques are required for a remote management of an IMD. The inventiondescribed herein addresses the need for verification thatinstruction(s)/program(s) sent to the IMD are properlyreceived/installed, and that the IMD functions properly after receipt ofthe instruction(s)/program(s). Robust encryption/decryption techniquesto prevent unauthorized access to the IMD, are also described herein. Inconjunction with outside access to the IMD, optional IMD owner consentmethods are also described.

Features of the Invention

1) A multi-repeater communications system/network which allows for (a)maximization of signal quality on a dynamic basis, (b) maximization ofuser freedom and (c) minimization of IMD battery drain.

2) Implantable communications repeater units are a possibility.

3) Wearable Repeater Units (e.g. WD) are a possibility.

4) RFIDs as locating device and/or repeater device are a possibility,including (but not limited to) the battery-less type of RFID; includingbut not limited to implantable RFIDs and RFIDs embedded in clothing andpersonal items (wallet, “pocket book,” “handbag” etc.).

5) Cell phone as communications repeater unit is a possibility.

6) Repeater Units with loss/misplacement detection, based on patterns ofmotion, GSR analysis and temperature analysis

7) IMD owner notification in the event of an actual or a potentialcommunications fault. One or more of the repeater units may also includea notification function, (or notification may be via a stand-alonenotification device).

8) Interactive IMD owner notification system

9) Use of motion detection apparatus in PMs and ICDs for communicationsmanagement

10) Use of MD/A/P in repeater units for communications management

11) Multimodal motion detection including (a) signal quality, (b) GPSand (c) MD/A/P and use of the position/motion/acceleration information,signal quality information and handshake information to optimizecommunications

12) Handshake format which manages communications, for use with thesystem

13) Architectures are possible with repeater units (a) in series, (b) inparallel, (c) in a network with both series and parallel elements

14) Dynamic communication system architecture: As needed, acommunications unit can be bypassed, a communications route can bealtered, a channel can be switched, a communications mode can bealtered. Both series and parallel communication elements may beincorporated into the communications network.

15) Communication systems are possible with:

-   -   a) local communications management: i.e. each communications        unit co-manages itself and its neighbors;    -   b) global communications management: i.e. one communications        unit manages all others; and    -   c) regional communications management: i.e. two or more        communications units each manage a group of local communicating        units.

16) Use of battery capacity for communications management decisions

17) System for verification of proper transmission of aninstruction/program from CS to IMD

18) Systems for verification of proper functioning of an IMD with a newinstruction/program

19) Static systems for highly secure encryption/decryption keygeneration and maintenance for the management of IMDs which are remotelyaccessible

20) Dynamic systems for highly secure encryption/decryption keygeneration and maintenance for the management of IMDs which are remotelyaccessible

21) IMD owner notification in the event an instruction/program needs tobe installed, and an IMD owner permission granting algorithm

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a system of repeater units linking acentral station to an implantable medical device.

FIG. 2 is a representational diagram showing stationary and mobilerepeater units in the environment of the IMD patient.

FIG. 3 is a representational diagram showing a patient with an IMD, aninternal repeater unit, and multiple external repeater units.

FIG. 4 is a representational diagram showing an IMD with attached RFIDs.

FIG. 5 is a representational diagram showing a wrist communicationsdevice.

FIG. 6 is a block diagram showing handshake signals exchanged betweencommunication units of the system.

FIG. 7 is a flow diagram showing communication management by an upstreamunit using a counter.

FIG. 8 is a flow diagram showing communication management by an upstreamunit using a timer.

FIG. 9 is a flow diagram showing communication management by andownstream unit using a timer.

FIG. 10 is a flow diagram showing the use of battery reserve assessmentto manage communications.

FIG. 11 is a representational diagram showing a possible geometricrelation between the distance from a signal source and the quality ofthe received signal.

FIG. 12 is a flow diagram showing the use of GPS information, andinformation about the quality of a signal which originates upstream, tomanage communications at the downstream end.

FIG. 13 is a flow diagram showing the use of GPS information, andinformation about the quality of a signal which originates downstream,to manage communications at the upstream end.

FIG. 14 is a flow diagram showing notification of patient, neighbor,central station administrator etc. in the event of suboptimalcommunication quality.

FIG. 15 is a flow diagram showing externalization of signals which carryinformation about patient motion detected by an IMD.

FIGS. 16A and 16B are flow diagrams showing algorithms for theassessment and reporting motion of an IMD.

FIG. 17 is a flow diagrams showing another algorithm for the assessmentand reporting motion of an IMD.

FIG. 18 is a block diagram showing the interrelationship among andnomenclature for describing an implantable medical device, amultiplicity of communication relay units including a final/mostupstream communication relay unit, a stationary unit and a centralstation which comprise a system which may communicate with and remotelycontrol and IMD.

FIG. 19A shows one possible geometric relationship between threeadjacent communication units that favors bypassing the middle one of thethree units.

FIG. 19B shows three block diagrams of exemplary systems comprising anIMD and multiple communication relay units: a) one in which only the IMDhas motion detection capability, b) one in which the IMD and allcommunication relay units have motion detection capability, and c) onein which some but not all of the mobile units of the system have motiondetection capability.

FIG. 20 is a flow chart illustrating the operation of an implantablemedical device in a communications system in which all mobile units havemotion detection capability.

FIG. 21 is a legend showing the interrelationship of FIGS. 21A and 21B,which comprise a flow chart illustrating the operation of a repeaterunit in a communications system in which all mobile units have motiondetection capability.

FIG. 22 is a legend showing the interrelationship of FIGS. 22A and 22B,which comprise a flow chart illustrating the operation of the mostupstream repeater unit in a communications system in which all mobileunits have motion detection capability.

FIG. 23 is a flow chart illustrating the operation of a stationarycommunications unit, in a system in which an implantable medical devicemay communicate with a remote station.

FIG. 24, is a legend showing the interrelationship of FIGS. 24A, 24B and24C, which comprise a flow chart illustrating the operation of animplantable medical device which has motion detection capability, in acommunications system in which any of the mobile units may or may nothave motion detection capability.

FIG. 25 is a legend showing the interrelationship of FIGS. 25A, 25B,25C, 25D, 25E and 25F, which comprise a flow chart illustrating theoperation of a repeater unit in a communications system in which any ofthe mobile units may or may not have motion detection capability.

FIG. 26 is a legend showing the interrelationship of FIGS. 26A, 26B,26C, and 26D, which comprise a flow chart illustrating the operation ofthe most upstream repeater unit in a communications system in which anyof the mobile units may or may not have motion detection capability.

FIG. 27A is a flow chart illustrating the operation of an implantablemedical device which does not have motion detection capability, in acommunications system in which one or more other mobile units havemotion detection capability.

FIG. 27B is a flow chart illustrating the operation of a repeater unitwhich does not have motion detection capability, in a communicationssystem in which one or more other mobile units have motion detectioncapability.

FIG. 27C is a flow chart illustrating the operation of a most upstreamrepeater unit which does not have motion detection capability, in acommunications system in which one or more other mobile units havemotion detection capability.

FIG. 28 is a block diagram showing parallel communication paths betweentwo communication units.

FIG. 29A is a block diagram showing a communication network with bothseries and parallel communication elements.

FIG. 29B is a matrix of 28 values which indicate communicationconditions between certain pairs of the communication elements shown inFIG. 29A.

FIG. 30 is a block diagram showing incoming signals to a communicationsunit.

FIG. 31A is a block diagram showing a system of communication units withmemory elements, for downstream transmission of instructions originatingfrom a central station.

FIG. 31B is a block diagram showing a system of communication units withmemory elements, for upstream transmission of a copy of instructionsoriginating from a central station.

FIG. 32 is a flow diagram showing an algorithm for determining whetherthe instructions transmitted from a central station arrived at theirdownstream destination in an uncorrupted form.

FIG. 33 is a block diagram of an IMD in which the receipt of newoperating instructions can be tested by running mock scenarios.

FIG. 34 is a block diagram of another embodiment of an IMD in which thereceipt of new operating instructions can be tested by running mockscenarios.

FIGS. 35A, 35B and 35C are block diagrams showing the setting up ofencryption and decryption keys for the IMD and for the unit whichcommunicates with the IMD.

FIG. 36 is a representational diagram showing an array of portablememory units, each of which contains an encryption/decryption key forone IMD.

FIG. 37 is a block diagram showing a system with two differentencryption/decryption keys, one for each source of possible IMD remoteinstruction generation.

FIGS. 38A and 38B are block diagrams showing two types of apparatus forthe generation of an encryption/decryption key based on patient data.

FIG. 39 is a graphical representation of a cardiac electrogram, the timedependent voltage of which is used to generate an encryption/decryptionkey.

FIG. 40 is a flow diagram illustrating a method by which the IMD ownermay grant permission to download/install an instruction, program orcommand to an IMD.

FIG. 41 is another flow diagram illustrating a method by which the IMDowner may grant permission to download/install an instruction, programor command to an IMD.

FIG. 42 is yet another flow diagram illustrating a method by which theIMD owner may grant permission to download/install an instruction,program or command to an IMD.

FIG. 43 is a block diagram illustrating a medical device system withlocator units, with one type of locator configuration.

FIG. 44 is a block diagram illustrating a medical device system withlocator units, with a second type of locator configuration.

FIG. 45 is a block diagram of a medical device system with communicationunits which detect changes in spatial position, illustrating thepropagation of coordinate information pertaining to such units.

FIG. 46 is a block diagram of a medical device system with communicationunits which detect changes in spatial position, illustrating thepropagation of communication optimization information pertaining to suchunits.

FIG. 47 is a block diagram of a medical device system with communicationunits which detect changes in signal quality, illustrating thepropagation of signal quality information pertaining to such units.

FIG. 48 is a block diagram of a medical device system with communicationunits which detect changes in signal quality, illustrating thepropagation of communication optimization information pertaining to suchunits.

FIG. 49 is a block diagram illustrating the determination of an optimalcommunication route by a local or master communication control unit.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a block diagram which shows the possible routes ofcommunication between a central station (CS) and an implanted medicaldevice (IMD). Four relay units are shown between the CS and the IMDincluding a stationary unit (SU), cell phone device (CPD), a wristdevice (WD) and a radiofrequency identification device (RFID). The solidand broken lines between the units indicate the path of a signal whichlinks the CS and the IMD.

The four relay units are shown by way of example, and numerous otherexamples are possible including those with a) more relay units, b) fewerrelay units, c) with more of one kind of unit, d) fewer or none ofanother kind, and e) in which the sequence of relay units differs.Stationary units are in a fixed location and may have a hard-wiredconnection to a public telephone system or a connection (hard-wired ornot) to an internet-based telephone system.

Cell phone devices are not hard wired and may be a commercialoff-the-shelf unit with capability to simultaneously communicate withtwo other units. Alternatively, it may be a modified cellular phoneunit, optimized for function in the capacity discussed hereinabove andhereinbelow. The cell phone's special value is that the likelihood thatit is near to a person at any one time is greater than would be the casefor a stationary unit (e.g. a SU located in the patient's home).

The wrist device (which may be located on other patient body parts otherthan the wrist—e.g. ankle, chest, etc.), also is of value because of thehigh likelihood of patient proximity. Because it may be even closer tothe patient than a cell phone, the energy expenditure for communicatingwith it from a downstream device (i.e. a device which is the IMD, or andRFID) may be even less than that required for communication between thedownstream device and the cell phone.

A variety of RFIDs are possible including a) external RFIDs, and b)internal RFIDs. The RFID may be a passive unit, a semi-passive one, anactive one or a beacon type. These are intended to be in very closeproximity to the IMD, and therefore to result in very minimal drain onthe IMD battery if communication is required between the IMD and theRFID. Furthermore, RFIDs allow the system to locate an IMD by assessingthe location of the IMD-companion (i.e. the RFID, or a wrist device).This approach also avoids draining the IMD battery during locatingefforts.

The communication route from CS to IMD need not be the same as that fromIMD to CS. Furthermore, the route of either or both legs may vary duringthe course of one communication session.

Any particular device may provide a locator function, a relay functionor both. For example, in one embodiment of the invention, an RFID mayperform a locator function in conjunction with an SU, while the same SUcommunicates with the IMD via the CPD.

The table below shows examples of systems with 1, 2 and 3 repeaterunits. In the example in the table, the RFID may function as a repeaterunit.

Examples of IMD-CS Communication System Elements with One to ThreeRepeaters

Patient First Second Third Unit Repeater Repeater Repeater Control UnitIMD RFID CS IMD WD CS IMD CPD CS IMD SU#1 CS IMD SU#2 CS IMD RFID WD CSIMD RFID CPD CS IMD RFID SU#1 CS IMD RFID SU#2 CS IMD WD CPD CS IMD WDSU#1 CS IMD WD SU#2 CS IMD CPD SU#1 CS IMD CPD SU#2 CS IMD RFID WD CPDCS IMD RFID WD SU#1 CS IMD RFID WD SU#2 CS IMD RFID CPD SU#1 CS IMD RFIDCPD SU#2 CS IMD WD CPD SU#1 CS IMD WD CPD SU#2 CS

FIG. 2 shows a patient with an IMD, his home which contains SU-1A andSU-1B, and his office with another stationary unit, SU-2. The patient(with IMD seen in detailed view) is in a car and his CPD is in the carwith him. The figure is intended to illustrate the concept that bypopulating the patient's environment with enough stationary and mobilecommunication devices, the patient's IMD may be within very close rangeof a communications device at all times.

FIG. 3 illustrates the same concept, but does so for the very immediateenvironment of the patient. A cell phone device is in the patient'sshirt pocket. EIDs (external RFIDs) are shown on or in the patient'sbelt, on or in a shirt and pants. In the case of a female patient, theycould be in a blouse or skirt, if desired. In addition, an IID (animplanted RFID) is also shown. The IID could be part of the IMD, couldbe separate from the IMD but in close proximity to it (or touching it)or could be implanted elsewhere in the body of the IMD owner (i.e. theperson in whom the IMD is implanted). In addition, a wrist device isshown on the patient's wrist. This is an exemplary figure, and it isunlikely that any one person would have or need the large number ofrelay devices shown in the figure. Other possible locations forcommunication devices include an ankle bracelet, a device in a patient'swallet, a device in a handbag, pocketbook, fanny-pack, necklace,eyeglasses or hearing aid.

FIG. 4 shows an example of an IMD with three RFIDs attached to it. Theintention of the figure is to illustrate a number of possible RFIDlocations. The RFID would not be powered by the device; Communicationcircuits which are directly powered by the IMD are considered to be partof the IMD. If the IMD is an ICD, the following additionalconsiderations obtain:

-   -   Care would be taken to prevent damage to the RFID at the time of        defibrillator discharge;    -   Care would be taken to prevent the IMD from effectively        decreasing the conductive surface area of the can of the ICD to        the extent that the transcardiac voltage and current gradients        would be meaningfully altered; and    -   It might be possible for the IMD to passively obtain some energy        for self supply at the time of an ICD discharge.

FIG. 5 shows a wrist device. On the upper surface, a keypad andinformation screen are shown. The keypad function may be incorporatedinto the screen via touch-sensitive screen technology. A communicationsunit allows the WD to function as both a relay device and as a patientlocator device. An optional GPS device could assist with the locatorfunction. The contact electrodes assure that the device is being worn bythe patient. In the absence of contact, the device itself may signal thepatient (e.g. with a sound), or the device may communicate with anotherdevice in the patient's environment (e.g. CPD) to let the patient knowthat the WD is not being worn. The processor/memory/controller controlsthe transmitter, the receiver, the information screen and the audiocircuits, may store partially or completely transmitted informationbeing sent in either the upstream or the downstream direction, may storeencryption/decryption information, monitors and tests WD performance andperforms other functions familiar to those skilled in the art. Themicrophone and speaker allow audio communication between the device andthe wearer [e.g. a) to tell the patient that he is moving out of rangeof reliable communications, b) to allow a medical professional in a CSto speak with the patient, and c) to notify the wearer of a need forservice of the WD itself]. Embodiments of the WD with fewer of thesefunctions are possible. Proper communication between CS and IMD ismonitored and enhanced by a number of features discussed in conjunctionwith FIGS. 6 through 24B. The exchange of beacon or handshake signalsbetween adjacent or non-adjacent units is shown in FIG. 6, and isdiscussed in the specifications of U.S. Pat. No. 7,277,752 and U.S.patent application Ser. Nos. 11/502,484, 11/895,934, and 12/154,079.Referring to FIG. 6, the word “upstream” refers to the direction fromthe IMD to the CS, and the word “downstream” refers to the directionfrom the CS to the IMD. Using this terminology, for example, the CPD isdownstream from the SU but upstream from the IMD. One therefore mayrefer to three communication units that lie between the CS and the IMD(and which may include the CS and the IMD) as upstream, midstream anddownstream, where the word “midstream” refers to a communications unitwhich lies between an upstream and a downstream unit. An example of anupstream, midstream and downstream unit is an SU, a CPD and a WD,respectively. Another example is the CS, a SU and a CPD, respectively.At times, hereinbelow, an upstream unit is referred to as an “alpha”unit and a downstream unit is referred to as a beta unit.

In the terminology used herein, S1 signals are beacon or handshakesignals sent from any unit to another further downstream, requesting aresponse from the downstream unit, while S2 signals are the response.The signals may involve adjacent units (e.g. the upstream and midstreamunit), or non-adjacent units (the upstream and downstream units). Theremay be a 1:1 relationship between the number of S1s and the number ofS2s (the format of U.S. Pat. No. 7,277,752), or a many to onerelationship (discussed herein). Other types of communicationinformational signals (discussed hereinbelow) may be exchanged as partof the process of communications enhancement (e.g. downstream unitindicates to upstream unit that S1 intensity is declining). Other typesof communication management protocols and numerous variations will befamiliar to those skilled in the art.

FIG. 7 shows an example of an algorithm for handshake management at anupstream communications unit, in one format for communication between anupstream and a downstream communication unit: Beacon signals—referred toherein as “S1”s—are emitted by the upstream unit, after which theupstream unit determines whether a response to the S1—by the emission ofan “S2” signal by a downstream unit which has received the S1 signal—hasoccurred. In the FIG. 7 algorithm, a satisfactory response to therepetitive S1 beacon signals is the receipt of at least one S2 out ofevery Z emitted S1s, where Z is an integer. The “allowed S1-S2 delay” inthe figure determines the extent of time allowed for an S2 responseafter an S1 is emitted. The S1-S1 frequency may be determined by either:

a) the sum of the allowed S1-S2 delay and the “S2-S1 delay”; or

b) the sum of the actual S1-S2 interval and the S2-S1 delay.

Possible management options for non-response after Z and after Z+n S1sare shown in FIG. 7.

Other algorithms are possible with which:

a) there are fewer or more options in each “tier” or group of options,where the first tier in the current algorithm is defined as the regimewherein the value of counter A ranges from Z up to Z+n−1, and the secondtier in the current algorithm is defined as the regime wherein the valueof counter A is greater than or equal to Z+n;

b) some of the options listed for the first tier (value of counter Abeing>the number Z), are instead listed for the second tier (value ofcounter A being>or equal to the number Z+n);

c) option A7 is instead listed for the first tier;

d) Z is the number “1”, in which case one S2 is expected for each S1;

e) Z is a non-fixed number, whose value may depend on one or more otherparameters (e.g. GPS related information, the importance of atransmission as indicated by the sender, recent communication historydetails etc.);

f) n is a non-fixed number, whose value may depend on one or more otherparameters (e.g. GPS related information, the importance of atransmission as indicated by the sender, recent communication historydetails etc.); and/or

g) there are fewer or more tiers.

FIG. 7 also indicates possible responses to an “S1 not received” signalfrom a downstream unit.

FIG. 8 shows an example of an algorithm for handshake management at anupstream communications unit, in another format for communicationbetween an upstream and a downstream communication unit: In this format,a handshake interruption is indicated at the upstream unit bynon-receipt of an S2 response after a certain amount of time (as opposedto the case shown in FIG. 7, i.e. non-receipt of an S2 response after agiven number of S1s). S1s are continuously emitted. When receiveddownstream; the downstream communications unit returns an S1.

If an S2 is not received within the ordinarily expected interval(designated J₁ in the figure), options B0 to B6 are possible choices. Ifan S2 is still not received by time J₂ then options B7, B8 and B9 arepossible choices. If an S2 is still not received after an additionalinterval of K, then any of options B0 to B7, and B9 are possible, andeach may be repeated every K seconds thereafter until an S2 is received.

Other Algorithms are Possible with:

a) fewer or more options in each “tier”, where the definition of tier isanalogous to that of FIG. 7, i.e. a group of options available for agiven contingency, e.g. options B0 through B6;

b) some of the options listed for the first tier are instead listed forthe second tier;

c) one or more of options B7 and B9 are instead listed for the firsttier;

d) The value of J₁ is equal to the value of the S1-S1 interval, so thatone S2 is expected for each S1;

e) J₁ is a non-fixed value, which changes from circumstance tocircumstance, whose value depends on one or more other parameters (e.g.GPS related information, the importance of a transmission as indicatedby the sender, recent communication history details etc.);

f) J₂ is a non-fixed value, which changes from circumstance tocircumstance, whose value depends on one or more other parameters (e.g.GPS related information, the importance of a transmission as indicatedby the sender, recent communication history details etc.);

g) K is a non-fixed value, which changes from circumstance tocircumstance, whose value depends on one or more other parameters (e.g.GPS related information, the importance of a transmission as indicatedby the sender, recent communication history details etc.); and/or

h) fewer or more tiers.

FIG. 8 also indicates possible responses to an “S1 not received” signalfrom a downstream unit.

FIG. 9 shows an example of an algorithm for handshake management at adownstream communications unit, in a format for communication between anupstream and a downstream communication unit which is complementary tothat of FIG. 8 (i.e. FIG. 8 shows a complementary upstream algorithmwhich could be used with the downstream algorithm described herein).

In this format, a handshake interruption is indicated at the downstreamunit by non-receipt of an S1 after a certain amount of time since thelast received S1. S1s are continuously emitted by the upstream unit.When an S1 is received downstream; the downstream communications unitreturns an S2, and also starts a timer which allows for determination ofwhether the next S1 is received within an interval L which equals theS1-S1 interval. (The S1-S1 interval may be an industry standard or maybe signaled to the downstream unit previously by the upstream unit.) Ifthe next S1 is received within the time L, the timer of this downstreamunit is reset; if not, options C0 to C8 are possibilities.

Other Algorithms are Possible with:

a) fewer or more options in the event of a non-received S2;

b) L is a non-fixed value, which changes from circumstance tocircumstance, whose value depends on one or more other parameters (e.g.GPS related information, the importance of a transmission as indicatedby the sender, recent communication history details etc.); and/or

c) more tiers.

FIG. 9 also indicates possible responses to an “S2 not received” signalfrom an upstream unit.

Careful management of the energy which remains in the battery orbatteries of a portable device, and especially careful management of theenergy which remains in the battery or batteries of an implanted deviceare important to maximize the duration of use of these devices (beforerecharge, battery replacement, or device replacement is necessary). Suchmanagement is one of the subjects of the patent and applicationsincorporated herein by reference. FIG. 10 herein shows an algorithm thatallows for using measurements of battery reserve to:

a) decrease power consumption, if possible,

b) notifying the IMD owner and/or the CS of a declining level of powerreserve, and

c) if necessary, bypassing a communications unit with a failing battery.

The algorithm calls for the monitoring of “battery voltage” but otherparameters of battery reserve could be used including:

a) the impedance of one or a combination of the individual batteries, ifthere is more than one;

b) the duration of time since the battery was either charged, replacedor installed; and

c) a summation of current drain (as a function of time) multiplied bythe time of such current drain, i.e. to generate an estimate of thenumber of amp-hours that a battery has been used while taking intoaccount that current drain is not constant.

Furthermore, voltage details could be examined including:

a) the voltage of one or a combination of the individual batteries, ifthere is more than one;

b) the voltage at times that the unit is quiescent, or relative so; and

c) the voltage at times of relatively high power drain (e.g. during highvoltage capacitor charging of an ICD, or at times that transmitter poweris maximal).

FIG. 10 shows a two tiered approach to using battery reserve informationfor device/system management. Power consumption may be managed bydecreasing the power output during transmissions or decreasing the rateat which handshake or other “housekeeping” signals are exchanged. Othermethods of power savings include less storage and analysis ofnon-essential information. The user may be notified by either a messagedelivered (see hereinbelow in conjunction with FIG. 14) from the devicewith the declining battery reserve, or by a message sent from the devicewith the low reserve to another device which performs the notificationfunction (e.g. a wrist device with declining battery voltage notifiesthe cell phone device of same, which in turn notifies the user). Thepurpose of the optional delay is shown in the figure to modulate thefrequency of notification of low voltage or reaction to it.

Embodiments of the invention are possible with:

a) fewer or more tiers than the number shown in the figure;

b) no monitoring of battery reserves;

c) a substantially continuous relationship between battery reserve andpower consumption, rather than a stepwise one; and

d) sharing the information about battery reserves with either (i) theadjacent communication units [defined hereinbelow in conjunction withFIG. 18], (ii) a communication unit which has been designated as eitherthe local communications controller or the system communicationscontroller [see hereinbelow].

Other techniques for battery conservation and management will beapparent to those skilled in the art.

FIGS. 11-13 show how the analysis of:

a) the relative positions of two communicating units;

b) relative movement of two communicating units;

c) the strength of the received signal at each respective unit; and/or

d) the rate of change in signal strength.

may be used to optimize communications between the two units.

FIG. 11 shows an example of a method of categorizing the relativepositions of two communicating or potentially communicating units. Thelocation of one such unit is indicated by the square in the center ofthe figure. If the location of the second such unit is within Zone 1,i.e. near the first unit, then one expects that signal quality at eachof the two units should be good. If the second unit is in Zone 2, oneexpects less signal strength at each of the two receivers than is thecase for the second unit being in Zone 1; etc. for Zones 3, 4, 5 and 6.FIG. 11 shows one of an essentially infinite number of possibleexamples. Variations include:

a) a greater or lesser number of zones;

b) a substantially continuous relationship between the distance betweencommunicating units and a parameter (e.g. output power) which isadjusted based on distance;

c) zones which may all be the same width, zone widths which bear analgebraic relationship to distance (e.g. width of zone decreases as thesquare or cube of the distance); or zone widths which have anon-algebraic relationship to distance, or no relationship to distance;

d) zone shapes which may not be radially symmetric, and some or allzones which are shaped differently than other (or all other) zones; and

e) zone shapes and/or sizes which are constant in time vs. zone shapesand/or sizes which vary with time (e.g. variation as battery reservefalls or variation as the device/device antenna orientation varies, asweather varies, as sunspot conditions vary and/or as obstacles vary).

In one or more embodiments of the invention, a zone-based and/ordistance [between communicating units]-based format:

a) may not be used at all (e.g. a format based on signal strength orchange in signal strength may be used);

b) may be used intermittently; or

c) may be used as one of a number of parameters which are inputted inthe optimization of communications.

FIG. 12 shows an algorithm which uses both GPS information and signalstrength information to optimize communications at the downstream orbeta end of a communicating pair of devices (e.g. IMD and WD).Algorithms are possible which use only GPS information, only signalstrength information, both, or either one or both plus additionalinformation (e.g. battery reserve, urgency of transmission, etc.). Forboth position and signal strength, algorithms are possible in which therate of change of either of these parameters:

a) is used along with the parameter itself;

b) is used instead of the primary parameter; or

c) is not used at all.

Algorithms are also possible in which a higher order derivative ofeither parameter is used, e.g. acceleration (i.e. the second derivativeof position with respect to time) alone, or in addition to the otherparameters mentioned herein.

Signal quality has been divided into “good”, “fair” and “poor”. Inaddition a slowly deteriorating signal has been classified as fair, anda rapidly deteriorating one has been classified as poor. Similarly,distance has been classified as good, fair and poor; and a slowlyincreasing distance has been classified as fair, while a rapidlyincreasing distance as poor. Algorithms are possible in which theinformation concerning rates of change of position and signal strengthare used in different ways than in the algorithm in the example; manysuch approaches will be obvious to those skilled in the art.

The pentagon symbol in FIGS. 12 (and 13) is conceptually similar to thatof a diamond-shaped object in a flow diagram: It indicates threepossible choices (the lower three corners) where the choice is made bycomparing a) information inputted at the upper left corner with b)information inputted at the upper right corner. Thus, the pentagon shapein FIG. 12 indicates that the information from the onboard GPS (i.e. thebeta unit's GPS) is compared with information which was transmitted fromthe upstream (alpha unit's) GPS: If the comparison shows that therelative positions are in a good range, then the left-most corner of thepentagon leads to options E11 through E13. If the comparison shows thatthe relative positions are in a fair range (or are slowly separating),then the right-most corner leads to options E0 through E6. If thecomparison shows that the relative positions are in a poor range (or arerapidly separating), then the lower-most corner leads to options E7through E10.

Algorithms are possible with:

a) a greater number of tiers of classification and therapy;

b) a lesser number of tiers of classification and therapy;

c) the same “curative” options differently distributed among the tiers;

d) a smaller or larger number of curative options; and/or

e) different curative options.

FIG. 13 shows an algorithm which uses both GPS information and signalstrength information to optimize communications at the upstream or alphaend of a communicating pair of devices (e.g. IMD and WD). Thedifferences, therefore between FIGS. 12 and 13 are related only to this,and reflect the complementary nature of the two. For example, the inputsare reciprocally different, e.g. in FIG. 12, the downstream unit looksat the signal strength of the S1, while in FIG. 13, the upstream unitlooks at the signal strength of the S2. For the same reasons, someremedies are changed reciprocally—e.g. FIG. 12 has option E3 as anincrease beta unit's power output, while FIG. 13 has an increase alphaunit's power output as option E3. Embodiments of the invention in whichthe algorithms are not reciprocally related are possible, e.g. in whichthe options for poor signal quality at the alpha unit are different thanthe options for poor signal quality at the beta unit.

Referring to both FIGS. 12 and 13, options E1, E7, F1 and F7 involve“user” (i.e. the IMD owner) notification, and are further discussedhereinbelow, in conjunction with FIG. 14. Options E8 and F8 involvenotification of the central station (and perhaps, thereafter, theuser/IMD owner). Options E2-E5, E9, E12, E13, F2-F5, F9, F12 and F13involve modification of communications with one of the two adjacentcommunicating units. Options E6 and F6 involve changes which may affectone or both adjacent units (e.g. bypassing a unit, as shown hereinbelowin FIG. 19A and discussed in conjunction with the associatedspecification), or even changes that affect units which are more distantthan the adjacent ones.

In the event of either:

-   -   a) deteriorating communication conditions (the deterioration        likely to concern the less robust        -   links, i.e. one or more of the links in the vicinity of the            IMD), or    -   b) an inability to communicate between IMD and one of the        repeater units in its vicinity,

then a means of notifying the IMD owner [i.e. the person in whom the IMDis implanted] is desirable.

Notification is discussed generally first, and an exemplary algorithm isdiscussed hereinbelow in conjunction with FIG. 14.

The notification itself may be delivered:

-   -   a) by a phone call to the IMD owner's CPD;    -   b) by a verbal announcement coming from a WD or CPD (e.g. a        previously stored voice prompt);    -   c) by a tone, chime, vibration, screen message, flashing light        source, etc. from a WD or CPD; or    -   d) by a tone, chime, buzzing, computer screen message,        television screen message, flashing light source, etc. from a        stationary source in the IMD owner's home, workplace, motor        vehicle, or any other place likely to be frequented by the IMD        owner; or    -   e) by any device or means which will attract the attention of        the IMD owner.    -   Alternatively (or if none of the above means is successful in        obtaining the attention of the IMD owner), notification of a        spouse, other family member (who preferably but not necessarily        live with or near the IMD owner), neighbor or colleague in the        workplace may be attempted.    -   FIGS. 7-12 hereinabove each indicate contingencies in which the        notification of the IMD owner may be desirable:    -   a) a handshake failure between communication units detected at        an upstream unit, e.g.:    -   i) option A6 [FIG. 7], due to counter A equaling exceeding the        value of Z;    -   ii) option A8 [FIG. 7], due to counter A equaling or exceeding        the value of Z+N;    -   iii) option A7 [FIG. 7] (exercised via the CS), due to counter A        equaling or exceeding the value of Z+N;    -   iv) option B6 [FIG. 8], due to timer #1 exceeding the value of        J;    -   v) option B8 [FIG. 8], due to timer #2 exceeding the value of K;        or    -   vi) option B7 [FIG. 8] (exercised via the CS), due to timer #2        exceeding the value of K;    -   b) a handshake failure between communication units detected at a        downstream unit, e.g. option C7 [FIG. 9] due to beta timer        exceeding the value L;    -   c) a fall in battery voltage at the communications unit which        includes the notification mechanism, e.g. options D3 [FIG. 10]        and D5 [FIG. 10] (exercised via the CS);    -   d) a fall in signal quality at the notification device, e.g.        options E1 [FIG. 11], E7 [FIG. 11] and E8 [FIG. 11] (exercised        via the CS);    -   e) a fall in signal quality at the communications unit which is        upstream from the notification device, e.g. options F1 [FIG.        12], F7 [FIG. 12] and F8 [FIG. 12] (exercised via the CS);    -   f) a determination by the communications unit which includes the        notification device that the distance between it and the        upstream communications unit (as determined by GPS) is        suboptimal, e.g.:        -   option E1 [FIG. 11], due to distance slowly increasing or in            a somewhat marginal        -   range;        -   option E7 [FIG. 11], option E8 [FIG. 11] (exercised via the            CS) due to distance        -   rapidly increasing or in a very marginal range; and    -   g) a determination by the communications unit which includes the        notification device that the distance between it and the        downstream communications unit (as determined by GPS) is        suboptimal, e.g.:        -   option F1 [FIG. 12], due to distance slowly increasing or in            a somewhat marginal        -   range;        -   option F7 [FIG. 12], option F8 [FIG. 12] (exercised via the            CS) due to distance        -   rapidly increasing or in a very marginal range;

If a medical professional in the CS or elsewhere wishes to remotelyaccess the IMD, and the arrangement with the IMD owner is that the IMDowner's permission is required for such access (see hereinbelow), thenthe notification device may inform the IMD owner of a permissionrequest. The medical professional may indicate the level of urgency,which may influence the quality of the notification (see hereinbelow).

Other contingencies in which the notification of the IMD owner may bedesirable include:

a) a fall in battery voltage at a communications unit either upstream ordownstream from the unit which includes the notification mechanism [andreported to the unit which includes the notification mechanism];

b) the receipt of a signal by the communications unit which includes thenotification device that the distance is suboptimal between twocommunicating communication units, neither of which is that of thenotification device; and

c) the receipt of a signal indicating that the IMD owner's wrist deviceis no longer in contact with the IMD owner's wrist, as assessed by (i) achange in impedance between two contact electrodes, or (ii) a change intemperature sensed by the device.

FIG. 14 shows an algorithm in which a signal indicating one of theaforementioned contingencies requiring notification results in agradually more aggressive attempt to notify the device owner or, ifnecessary, the central station. In the approach shown in FIG. 14, thereare two levels of urgency of initial notification, with different typesof notification for the low level of urgency (e.g. soft tone) and for anintermediate level of urgency (e.g. loud tone).

The notification algorithm illustrated by FIG. 14 calls for an upgradeof the level of notification from low to intermediate in the event thateither:

-   -   a) there is no response by the IMD owner to a low level        notification; or    -   b) there is no correction of the low level fault by the IMD        owner within a certain time interval.

The notification algorithm calls for an upgrade of the level ofnotification from intermediate to high in the event that either:

-   -   a) there is no response by the IMD owner to an intermediate        level notification; or    -   b) there is no correction of the intermediate level fault by the        IMD owner within a certain time interval.

IMD owner notification for a consent is indicated as either low orintermediate urgency, because in a state of high urgency, it is possibleor likely that IMD owner consent might be bypassed. Nevertheless,consent formats (see hereinbelow) are possible in which the IMD ownermust agree to any and all outside access to his unit; With this format,a consent request of high urgency would be possible. An option such asG5 (louder longer tone) could be employed right from the start in such acircumstance.

Embodiments of the Device are Possible with:

-   -   a) a greater number of levels of urgency (and with an equal        number of corresponding qualities        -   of notification);    -   b) a lesser number of levels of urgency;    -   c) an algorithm in which the quality or type of notification at        one level of urgency may be the        -   same as that of another level (e.g. the intermediate level            results in production of the same        -   tone as that of the low level), and    -   d) different sensory effects than the sounds stated in the        figure.

The algorithm may be modified to allow either the IMD owner or the CSto:

-   -   a) turn off an alarm (e.g. in a situation in which it repeats        frequently);    -   b) modify the criteria for triggering the alarm;    -   c) modify the quality of the alarm; or    -   d) modify the amount of time before an alarm occurs (four such        intervals shown in the figure).

Many other notification algorithms are possible, and will be obvious tothose skilled in the art.

FIGS. 15-27C concern apparatus and methods for using the detection ofmotion of the IMD owner to reduce battery consumption. The concept is:If at one particular time, the communication quality between the twounits of the communication chain between IMD and CS is high, then, ifneither of the two units moves, the communication quality is likely toremain high. On the other hand, if one unit is moving with respect tothe other, then if the movement results in an increased distance betweenunits that communicate only over a short range, the communicationquality may decrease. In a no movement state, the reassessment ofcommunication integrity (e.g. the strength of a received signal, and/orthe response to a handshake signal) could occur on a less frequentbasis, or might be able to be carried out with a reduction in outputpower. On the other hand, in a state characterized by movement, it maybe desirable to increase the output power or the frequency ofreassessment of communication integrity, in anticipation of a possibleincrease in distance between communicating units.

The case of communication between the CS and an SU is a trivial one,since neither is likely to move. (By definition, an SU does not move,and only limited examples of a mobile CS [e.g. certain peripheral CSs,as defined in U.S. patent application Ser. No. 11/502,484] arepossible.) The units that are expected to move from time to time are theIMD itself, an internal RFID if part of the system, an external RFID ifpart of the system, a WD if part of the system, and a CPD, if part ofthe system.

Many pacemakers and ICDs have so called rate responsive capability, e.g.can operate in pacing modes such as VVIR, DDDR, etc. Such units detectmotion by an onboard piezoelectric crystal, or by an accelerometer, anduse the information to modulate pacing rate. However, if informationabout detected motion was shared with an upstream unit (e.g. an RFID, aWD, or a CPD), then the upstream unit could decrease handshake frequencyor signal strength during times when the downstream unit is stationary,thereby conserving battery reserves. The IMD itself could use the motioninformation to minimize current drain for its own communicationmanagement (e.g. decrease power output if communications have been good,and if no detected IMD motion has occurred since the time of goodcommunications.) Including such motion detecting apparatus in a CPD, aWD or an RFID would be possible.

In principle, a communications unit with motion detecting apparatuscould be moving at a perfectly constant velocity away from another unitwith which it is communicating; Because the velocity in this citedexample is constant, neither a piezoelectric crystal nor anaccelerometer would detect motion. This would constitute a case wheremotion detecting apparatus fails to detect such motion. However:

-   -   a) There would have to be some acceleration at the start of the        motion; and    -   b) Other systems in place (e.g. apparatus for examining signal        strength, response to handshake signals, or GPS signals) could        provide additional information which indicates that one        communication unit is moving with respect to the other.

FIG. 15 shows apparatus for performing this function. The optionaltiming circuits allow for the determination not only that motion isoccurring, but for the determination of a motion vs. time profile. Thetransmitter may transmit the information to the upstream and/ordownstream unit. Furthermore, the unit which contains the motiondetection apparatus may use the motion information for its owncommunication management. If the unit is a pacemaker or ICD, of course,the unit may further use the motion information for modulation of thepacing rate.

FIG. 16A shows a simple algorithm for the management of motioninformation. In the shown algorithm, if a motion parameter exceeds athreshold value, then the information is either a) sent to one or moreother communications units, or b) used by the device of which the motiondetection apparatus is a part. The motion parameter could examine a)maximum acceleration, b) acceleration above a certain threshold value,c) derived parameters of acceleration [e.g. acceleration squared]; Inaddition or instead, the motion parameter could examine time-relatedfunctions of acceleration, e.g. a) the average acceleration over aperiod of time, b) a time derivative of a smoothed accelerationparameter, etc. In addition or instead, the motion parameter couldexamine the output of a piezoelectric device or accelerometer device,such output related to the extent of acceleration. Other appropriateacceleration-based parameters will be obvious to those skilled in theart. Finally, acceleration could be examined along each of a number ofdifferent spatial axes. Each component of the multidimensionalacceleration information could then be used individually, or thecomponents could be blended to yield a single measure of acceleration.The delay shown in the figure is optional. The intention is to avoid, ifpractical, a continuous rebroadcast of acceleration information,especially if there is no change in the information with respect to theprior assessment. Embodiment of the invention are possible in which a)there is no delay; b) in which the delay is a fixed value, and c) inwhich the amount of delay depends on the magnitude of change in theacceleration parameter (i.e. small change leads to long delay).

FIG. 16B shows a simple algorithm for the determination of cessation orreduction in motion. Multiple approaches to reporting motion based onFIGS. 16A and 16B are possible including:

-   -   a) the approach shown in FIG. 16A could be used as the sole        determinant of motion,    -   b) the approach shown in FIG. 16B, in which non-motion (or        minimal motion, or a derived parameter which reports minimal        motion) is the sole reported item, or    -   c) an approach in which both motion and non-motion/minimal        motion (or derived parameters of each) are separately assessed        in parallel, as shown in FIGS. 16A and 16B.

Furthermore, families of algorithms such as that shown in FIG. 17 arepossible, in which a report of motion is not followed by another reportof motion until an intervening period of non-motion has been reported.Similarly, a report of non-motion is not followed by another report ofnon-motion until an intervening period of motion has been reported. Thisapproach also minimizes reporting and thereby may conserve batteryreserve. Many configurations of this series approach are possibleincluding:

-   -   a) those in which only positive activity signals are sent;    -   b) those in which only negative activity signals are sent;    -   c) those in which both positive and negative activity signals        are sent;    -   d) those with no delays;    -   e) those in which there is a single delay, which occurs at a        point other than after “MOTION PARAMETER<M2” (e.g. between        “SEND+ACTIVITY SIGNAL” and “MOTION PARAMETER<M2”);    -   f) those with multiple delays (e.g. before “MOTION PARAMETER<M1”        and before “MOTION PARAMETER<M2”); and    -   g) combinations of a)-f).

FIGS. 18-27C address the complexities of implementing the movementdetection system with a many unit communication system, i.e. a system asdescribed hereinabove in which there may be one or many communicationrelay units which are situated schematically between the IMD and the CS.In the related specification that follows, the sequence of topics is:

a) Nomenclature and Definitions;

b) General Principles;

c) Specific (Simple) Architectures;

d) Architecture in which All Movable Units have MDC; and

e) Architecture for a General System

Nomenclature and Definitions:

FIG. 18 shows an IMD which communicates with a central station. A seriesof relay units (from relay unit #1 to the final relay unit), eachintended to be a mobile unit, extend from the IMD to the firststationary unit. In an actual setup, there may be many relay units, onerelay unit or no relay units. Examples of relay units include CPDs, WDsand RFIDs. The final relay unit may communicate with a nearby SU, or maycommunicate directly with the CS.

The term “downstream” refers to the communication direction from the CSto the IMD; the term upstream” refers to the communication directionfrom the IMD to the CS.

As indicated in the figure, if a particular unit is designated as “relayunit U”, then the next unit immediate upstream (i.e. without anyintervening unit) is designated as “relay unit U+1”. For example, ifunit U is a WD, unit U+1 may be a CPD. The next upstream unit from relayunit U+1 is designated “relay unit U+2”, and the next upstream unit fromrelay unit U+2 is designated “relay unit U+3”.

The next unit immediate downstream from unit U (i.e. without anyintervening unit) is designated as “relay unit U−1”. For example, ifunit U is a WD, unit U−1 may be a RFID, or the IMD itself. The nextdownstream unit from relay unit U−1 is “relay unit U−2”, and the nextunit downstream from relay unit U−2 is designated “relay unit U−3”.

The term “adjacent” refers to two units which, using the nomenclatureand architecture shown in FIG. 18, communicate without an interveningunit. Thus units U+2 and unit U are each adjacent to unit U+1. The term“neighbor” refers to an adjacent communications unit; Thus units U+2 andunit U are each neighbors of unit U+1. Though the usual situation willbe that each unit communicates with its two adjacent neighbors, theremay be situations where one unit finds it easier to communicate with anon-adjacent one than with an adjacent one. For example, in a system inwhich the mobile units are an IMD, a WD (relay unit #1) and a CPD (relayunit #2), an IMD owner may be carrying his CPD in a pocket of hisclothing, but may have left the WD in a not nearby location. In thiscase, the IMD may have easier/better communications with the CPD thanthe IMD, and the communications path between the IMD and the CS couldthen be IMD←→CPD←→CS, rather than IMD←→WD←→CPD←→CS.

Motion detecting capability, “MDC” refers to a unit having the abilityto detect its own motion. Such ability could:

-   -   A) result from either of the types of motion detecting apparatus        that pacemakers and ICDs use, i.e. accelerometers or        piezoelectric crystal detectors, which hereinbelow are referred        to as “MD/A/P”;    -   B) result from a GPS-based system; or    -   C) be derived from signal strength information (i.e. If there is        a signal source of constant intensity at one location, and        signal detection apparatus at another location, then the        detection of a signal with gradually declining intensity over a        period of time, suggests that the detection apparatus and the        source are moving away from each other).

The “activity frontier” refers to the boundary between (i) one or moreadjacent moving units and (ii) a non-moving unit. An “upstream activityfrontier” is the boundary between (i) the most upstream moving unit of agroup of adjacent moving units and (ii) the next upstream neighbor,which is non-moving. A “downstream activity frontier” is the boundarybetween (i) the most downstream moving unit of a group of adjacentmoving units and (ii) the next downstream neighbor, which is non-moving.Thus, if the IMD owner is moving and is wearing a WD (and hence the WDis moving), and the IMD owner has a CPD which is nearby but isstationary, the upstream activity frontier is defined as the WD. If theIMD owner is at home with his CPD and neither are moving, but the IMDowner left the WD in a moving vehicle, then the WD is both the upstreamand the downstream activity frontier.

If none of the mobile elements are moving, the situation is referred toas a “quiescent state”. If there is incomplete information about whetherall elements are stationary, then an adverb may be added to define thelikelihood of a quiescent state, based on the number of non-movingelements, e.g. a “possibly quiescent state” if two mobile elements arequiescent, and a probably quiescent state if three mobile elements arequiescent.

General Principles:

(1) Use of Activity Information: Using motion information can help tooptimize communications between adjacent units and decrease batterydrain. If communication between adjacent units was of good quality attime t, then

-   -   a) it is likely to be of good quality at time t+x, if during the        interval between t and t+x the distance between adjacent units        did not increase, which is likely to be the case if neither of        the two adjacent units moved during the time interval; and    -   b) it is less likely to be of good quality at time t+x, if        during the interval between t and t+x the distance between        adjacent units increased, a condition whose likelihood is        increased if at least one of the two units moved.

(2) Techniques and Rationale for Locally Increasing CommunicationEfforts: In order to compensate for the motion of either of a pair ofcommunicating units, any one or more of a number of actions may be takento “increase the assiduousness of communication” between the units ofthis pair, including:

-   -   a) increase the power output of the upstream member of the pair        on the channel for downstream communications with its neighbor;    -   b) increase the power output of the downstream member of the        pair on the channel for upstream communications with its        neighbor;    -   c) increase the sensitivity of the upstream member to signals        from downstream;    -   d) increase the sensitivity of the downstream member to signals        from upstream;    -   e) increase the frequency of handshake signals between the two        communicating elements, e.g., increase the repetition rate of        S1s for the upstream element and/or increase the ratio of number        of S2s to number of S1s for the downstream element; and/or    -   f) if necessary, i.e. if during the period of motion signal        quality is decreasing, change the communications channel or mode        or route for communications between the upstream and the        downstream elements.    -   Other communication optimization approaches will be obvious to        those skilled in the art.

(3) Two Adjacent Units with Different Activity Profiles: The ActivityFrontier: If one member of a pair of adjacent units is moving and theother is not, then the link between these two is a preferred locus foran increase in the assiduousness of communications, by using one or moreof the approaches listed in (2) hereinabove. The rationale for theincrease in assiduousness is that it is possible that the detectedmovement may result in an increasing degree of separation between themoving and the adjacent non-moving unit. For example, if the IMD owneris wearing a WD which has motion detecting capability, (MDC), and theIMD owner is moving, but the CPD is not moving, then the WD/CPD junctionis a more vulnerable communications link, than it would be if neitherdevice was in motion. The WD would be considered the upstream activityfrontier, and efforts to locally increase the assiduousness ofcommunications would include:

-   -   a) increasing the power output of the CPD on the channel for        communications with the WD;    -   b) increasing the power output of the WD on the channel for        communications with the CPD;    -   c) increasing the sensitivity of the CPD to signals from the WD;    -   d) increasing the sensitivity of the WD to signals from CPD;    -   e) increasing the frequency of S1s from the CPD and/or        increasing the ratio of number of S2s to number of S1s at the        WD; and/or    -   f) if necessary, i.e. if during the period of motion signal        quality is decreasing, changing the communications channel or        mode or route for communications between the CPD and the WD.    -   It would also be possible to forgo doing all of a)-f) in the        event of detected motion.    -   If the IMD owner is moving, then the upstream activity frontier        defines the most upstream point of repeater units that are        carried by or moving with the IMD owner. Since the downstream        activity frontier is defined as the most downstream moving unit        among a number of adjacent moving units, in the case of a moving        IMD owner, the downstream activity frontier is the IMD. Since        the IMD has no downstream neighbor, in cases where the IMD owner        is moving, no adjustments need be made at the downstream        activity frontier. However, if a repeater unit (e.g. the CPD) is        accidentally left on a moving vehicle, and if the next        downstream unit (i.e. the WD) is not moving, then a downstream        activity frontier exists (in this case at the CPD), and an        increase in communications assiduousness at the downstream        activity frontier (i.e. for communications between the CPD and        the WD) is called for.

(4) Two Adjacent Units, Both of which are Moving: If both members of apair of adjacent units are moving, then there is a substantialpossibility that the two units are moving together (e.g. the IMD owneris wearing a wrist device, and begins to wall). Additional informationthat would support the two moving together includes:

-   -   A) The moment that movement begins for one member of the pair is        substantially the same as the moment that movement begins for        the other member of the pair;    -   B) If movement temporarily halts for one unit, it halts or is        substantially reduced for the other, in a similar time frame;        and it resumes for both in a substantially similar time frame;    -   C) If a third communications unit, adjacent to one of the two        units in the aforementioned pair has MDC, that third unit's MDC        also detects motion in a similar time frame to that for the        aforementioned pair of units;    -   D) If the two members of the pair both have GPS capability, then        movement of the two units substantially together could be        confirmed by comparing GPS information from each; and    -   E) If a signal of a given power is transmitted from one unit of        an adjacent pair and is received with signal strength which        remains constant over a period of time at the other unit of the        pair.

(5) No Increase in Communication Efforts at Junction of Two MovingUnits: If two adjacent units are both moving, then assuming [as per (4)above] that they are moving together leads to the conclusion that themeasures to increase the assiduousness of communication between them [aslisted in 2) above] should not be undertaken.

(6) Two Adjacent, Both of which are Not Moving: The Quiescent State: Ifboth members of a pair of adjacent units are not moving, then there is asubstantial possibility that:

-   -   A) additional mobile units, if any, are not moving; and    -   B) the IMD owner is not moving.

Additional information that would support a “quiescent state,” i.e. astate in which all mobile units are not moving is as follows:

-   -   A) If there is a third communications unit, adjacent to one of        the two units in the aforementioned pair, and that third unit        has MDC, and that third unit's MDC also does not detect motion,        then such non-detection of motion increases the likelihood of a        quiescent state.    -   B) If either of the two members of the pair (or both) have GPS        capability, then GPS information may be used to further define        the likelihood of a quiescent state. For example:        -   i) If a stationary state is reported from a GPS in one            member of the pair of units, and a stationary state is            reported from the other member of the pair of units by            MD/A/P, a possibly quiescent state may be concluded.        -   ii) If a stationary state is reported from GPS in each            member of adjacent units, then even if neither of these            units have MD/A/P, the conclusion of a possibly quiescent            state is warranted;        -   iii) Clearly, the certainty of determination of a quiescent            state increases with increasing numbers of detectors            reporting no motion. Thus if there are reports of no motion            from each of three detectors among a pair of units (e.g.            from a MD/A/P in one unit and a GPS in each of the two            units, or from a GPS in one unit and MD/A/P in each of the            two units), then the likelihood of a quiescent state is            greater than if there were two such reports. If both units            have MD/A/P and both units have GPS, and all four reports            indicate no motion, there is even greater certainty about            the conclusion of the existence of a quiescent state.    -   Note is made of the facts that the primary data from GPS is a        determination of the position of a unit, and that the primary        data from MD/A/P is the detection of an acceleration. Therefore:    -   a) Velocity information would have to be derived information for        a GPS-based determination—the calculation of which will be        obvious to those skilled in the art; and    -   b) In principle, one may have a state of substantially constant        velocity which would not cause the an accelerometer or        piezoelectric motion detecting apparatus to report a state of        activity. (In fact, perfectly constant linear motion should        cause no activity signal from either an accelerometer or        piezoelectric device, and small deviations from perfectly linear        motion may fall below the threshold for activity detection.)

In short, each of MD/A/P and GPS look at motion differently, and theirrespective analyses may complement each other.

-   -   C) If a signal of a given power is transmitted from one unit of        an adjacent pair and is received with signal strength which        remains constant over a period of time at the other unit of the        pair, this supports non-motion. Although a conclusion of        non-motion based on signal strength could, under certain        circumstances be inaccurate (e.g. if one unit is executing        angular motion with respect to the other), the monitoring of        signal strength has the advantage of leading to the suggestion        of some clearly remedial actions such as increasing either the        power output at the source or the sensitivity at the receiving        end. Other remedial actions will be obvious to those skilled in        the art.    -   Each of three modalities, (i) signal quality information, (ii)        GPS information, and (iii) MD/A/P information may be used alone        or in combination to assess whether a state of motion does or        does not exist. Furthermore, one or more motion detecting        modalities situated on two or more communicating units may be        used to determine whether the motion is local (e.g. the case of        a lost/misplaced unit [see hereinbelow]), or global (e.g. IMD        and WD and CPD moving together).

(7) Techniques and Rationale for Locally Decreasing CommunicationEfforts: If a determination is made that two or more communicating unitsare not moving (or are moving in a manner such that their relativepositions are fixed), then it may be advantageous to take measures todecrease the assiduousness of local communication efforts inanticipation of a stable spatial relationship between each pair ofnon-moving units. The decrease may save battery power, and decreasesensitivity to outside interference. Examples of specific actions toaccomplish this task include:

-   -   a) decreasing the power output of the upstream member of the        pair on the channel for downstream communications with its        neighbor;    -   b) decreasing the power output of the downstream member of the        pair on the channel for upstream communications with its        neighbor;    -   c) decreasing the sensitivity of the upstream member to signals        from downstream;    -   d) decreasing the sensitivity of the downstream member to        signals from upstream; and/or    -   e) decreasing the frequency of handshake signals between the two        communicating elements, e.g., decreasing the repetition rate of        S1s for the upstream element and/or decreasing the ratio of        number of S2s to number of S1s for the downstream element.    -   Other such approaches will be obvious to those skilled in the        art.

(8) Techniques for Communications Management when Not All Units haveMD/A/P: Approaches include:

-   -   a) looking further upstream, downstream, or in both directions:        -   i) If the activity status of unit U is unknown, then for            upstream communications, the activity status of unit U+1            gives suggestive (though not unequivocal) information about            the motion status of unit U; Further corroborating            information may be sought by examining the state of motion            of (I) unit U+2, (II) unit U−1, or (III) both units U+2 and            U−1. Thus if the activity status of unit U is unknown but            the activity status of both of units U−1 and U+1 are            identical, then it is even more likely that the activity            status of unit U is the same as that of unit U+1 (and of            unit U−1), than would be the case if only the activity            status of U+1 was available. Similarly, if the activity            status of unit U is unknown, then for downstream            communications, the activity status of unit U−1 gives            suggestive (though not unequivocal) information about the            motion status of unit U; Further corroborating information            may be sought by examining the state of motion of (I) unit            U−2, (II) unit U+1, or (III) both units U−2 and U+1.        -   ii) If the activity status of an upstream units is unknown,            then looking downstream may provide useful information about            the upstream state of motion. For example, if the activity            status of unit U is unknown, and the activity status of unit            U+1 is unknown, then for upstream communications, the            activity status of unit U−1 may be useful. Similarly, if the            activity status of unit U is unknown, and the activity            status of unit U−1 is unknown, then for downstream            communications, the activity status of unit U+1 may be            useful.        -   iii) If necessary looking even further upstream or            downstream may be useful.

For example, if the activity status of unit U is unknown, and theactivity status of unit U+1 is unknown, then for upstreamcommunications, the activity status of unit U+2 may give suggestive(though not unequivocal) information about the motion status of unit U;similarly, if necessary, looking two or more units downstream may proveuseful for downstream communications;

-   -   b) looking at GPS data and attempting to make a motion        determination based on that information;    -   c) looking at signal strength and attempting to make a motion        determination based on that information; and/or    -   d) combinations of a)-c)

(9) Lost or Misplaced Unit: If a communications unit has a motion statewhich is the opposite of both of its neighbors, it may be lost ormisplaced. There are two possible families of motion states that definethis condition:

-   -   a) If the activity sensor of a communications unit shows motion        while the activity sensors of each of the neighboring        communication units do not, then the unit associated with the        sensor indicating movement may be lost or misplaced. For        example: If the WD activity sensor shows that the WD is moving,        while (i) the IMD sensor shows no motion, and (ii) the CPD        sensor shows no motion, then the WD may have been left off of        the IMD owner in a location where it is subject to movement        (e.g. in someone else's automobile).    -   b) If the activity sensor of a communications unit shows no        motion while the activity sensors of each of the neighboring        communication units show motion, then the unit associated with        the sensor indicating no motion may be lost or misplaced. For        example, the IMD owner may have left the home, taking along his        CPD but accidentally leaving behind his WD.    -   Remedies for a lost/misplaced communications unit include:    -   a) notify the IMD owner (e.g. by sending a message via the CPD);    -   b) notify the CS; and/or    -   c) the two communications units which are adjacent to the        lost/misplaced unit (e.g. the IMD and the CPD, in the example        hereinabove) communicate with each other until the        lost/misplaced unit is returned to the vicinity of its neighbors        [see (10) hereinbelow];

(10) Bypass of a Communications Unit Possible: Under certaincircumstances, it may be advantageous to have one communications unitbypass its neighbor and communicate directly with a unit which isfurther upstream or downstream. Using the nomenclature definedhereinabove, this would entail a circumstance where, for example, unit Ucommunicates directly with unit U+2 (or U−2) or directly with unit U+3(or U−3). In the example, the bypass of unit U+1 (or U−1) could occurbecause U+1 (or U−1):

-   -   a) is lost or misplaced;    -   b) has a failing or failed battery; or    -   c) is geometrically situated such that a communication path        which bypasses U+1 (or U−1) is more efficient.    -   An example of c) would be, as shown in FIG. 19A, if the distance        between unit U+1 and either of its neighbors was large, while        the distance between unit U and unit U+2 was small.    -   Methods of determining that it would be desirable to bypass a        unit include:    -   a) the pattern of motion described hereinabove in paragraph (9)        [Lost or Misplaced Unit], i.e. a sequence of three adjacent        communication units whose motion is either (i) positive,        negative, positive, or (ii) negative, positive, negative;    -   b) the detection of a low battery voltage in a unit;    -   c) detection of geometric relationship between U, U+1 and U+2        which was given as an example immediately hereinabove by        either (i) GPS, and/or (ii) signal strength. In the case of        signal strength, the expected pattern would be:        -   I) good signal strength for communications between units U            and U+2; and        -   II) less than good signal strength for at least one of:    -   communications between units U and U+1, and    -   communications between units U+1 and U+2.    -   FIG. 19A shows an example of locations of units U, U+1 and U+2        in which illustrates the above, in which the bypass of unit U        and the direct communication of units U and U+2 would be        advantageous. The detection of the situation in which bypass        would be favorable could be because:    -   a) at unit U+2: there are poor quality S1s from unit U+1, but        -   i) at unit U+2: there are good quality S1s from unit U, and        -   ii) at unit U: there are good quality S2s from unit U+2;    -   b) at unit U: there are poor quality S2s from unit U+1, but        -   i) at unit U+2: there are good quality S1s from unit U, and        -   ii) at unit U: there are good quality S2s from unit U+2;    -   c) at unit U+1: there are poor quality S1s from unit U, but        -   i) at unit U+2: there are good quality S1s from unit U, and        -   ii) at unit U: there are good quality S2s from unit U+2;            and/or    -   d) at unit U+1: there are poor quality S2s from unit U+2, and        -   i) at unit U+2: there are good quality S1s from unit U, and        -   ii) at unit U: there are good quality S2s from unit U+2.

(11) Local vs. Central vs. Semi-Central Communication Control: FIG. 19A,and many of the algorithms illustrated hereinabove and hereinbelowillustrate local control, i.e. a particular communications unit usesinformation from itself and/or from an adjacent unit to adjustcommunications (e.g. poor quality of a received S1 at unit U results inan increase in the sensitivity of unit U to incoming S1s).

-   -   However, it would be possible to designate one communications        unit as a central control unit (which may or may not be the        central station), which receives one or more of (a) signal        quality data, (b) GPS data, (c) motion data, and (d) battery        information from one or more communication units (from all units        in a preferred embodiment of the invention), and uses some or        all of that information to determine a set of optimum values of        communication parameters (e.g. route, power output of each unit,        sensitivity of each unit, etc) for the entire system. These        optimum values may change from time to time (e.g. depending on        the locations of the communicating units). Furthermore, the        choice of which unit is to be the central control unit may        change from time to time (e.g. an upstairs SU may be the        appropriate choice when the IMD owner is on an upper floor of a        multi-floor home, while a downstairs SU may be more appropriate        once the IMD owner descends to one of the lower floors). The        selection of which unit is to be the central communications        -   may be fixed (e.g. always the central station),        -   may involve a preset sequence ([i] central station if            certain conditions obtain, if not, [ii] home SU, if not,            [iii] office [SU]), or        -   may involve a process whereby the choice is made at any            moment based on current system conditions (e.g. [i] the unit            which at any moment has the best communications with each of            the other units in the system, or [ii] the unit which is            most centrally located among the units, or [iii]            considerations based on battery reserve, or [iv] other            considerations, or [v] combinations of [i] to [iv]).    -   It would also be possible to designate each of two or more        communication units as a semi-central control unit. For example,        unit U might be the semi-central control unit for each of units        U−1, U and U+1; while unit U+3 might be the semi-central control        unit for each of units U+2, U+3 and U+4.

(12) Activity Signal Need Not Be All-Or-None: Implantable pacemakers andICDs with activity responsive modes (e.g. VVIR, DDDR) generally have agraded response to activity, i.e. within certain limits, more activityresults in greater upward adjustment of the pacing rate. The response toactivity may be linear or non-linear, over a certain range of heartrates. An activity threshold may be set which determines the sensitivityof the detection apparatus to motion. This is the state of the art, andmultiple preferred embodiments of the invention may incorporate some orall of these features. In the specification hereinbelow activitydetection is frequently referred to as an all-or-none phenomenon, butapproaches in which evaluate intensity of activity are possible.

-   -   For example: Certain patterns of low level motion may be part of        an in-home routine that require only a small step-up, if any, in        the assiduousness of communication, while higher level patterns        of motion may suggest that the IMD owner is leaving the home, or        is performing an unknown activity. The system may be programmed        to recognize this distinction in advance, or may have learning        programs, which, over a period of time, may learn to recognize        the distinction. For example, if a low level of activity during        the early morning and late evening hours consistently is not        associated with a significant decrease in unit-to-unit signal        amplitude, the system may learn to recognize that these events        are related to getting dressed and undressed, brushing teeth,        etc.    -   Other examples will be obvious to those skilled in the art.

(13) During the Unit-to Unit Exchange of Activity Information,Inter-Unit Communications are Assumed to be Intact. In the event thatthey are not, multiple remedies are available, including those discussedhereinabove in conjunction with FIGS. 7-10 and 12-13.

(14) Actual CS-to-IMD Communications and IMD-to-CS Communications UseCommunication Parameters Selected and Optimized During the CommunicationOptimization Routine. The vast majority of the life of an IMD is likelynot to require communication with a CS or MD. The communicationoptimization protocols described herein allow for frequentsystem/route/parameter optimization, so that if/when the moment arriveswhen there is need for a communication, the likelihood is very high thata high quality exchange of information between CS and IMD can occurimmediately. (See further discussion hereinbelow regarding storage ofoptimization information, especially in conjunction with FIG. 29B.)

-   -   Ongoing optimization of the link between the IMD itself and the        first repeater unit is a step that does consume some IMD battery        energy. Ways to limit such consumption are:    -   a) If there is a high level of certainty that the first repeater        unit will be in very close proximity to the IMD, then only very        infrequent confirmation of the operability of the IMD to first        repeater unit may be performed;    -   b) The type of asymmetric handshaking format between the first        repeater unit and the IMD with a ratio of many first repeater        S1s to few IMD S2s, would allow the IMD to not transmit unless        it failed to receive timely S1s.

Specific (Simple) Architectures

In FIGS. 19B-27C activity detection is assumed to be primarilyaccelerometer or piezoelectric crystal-based. The use of GPS and/orsignal strength data is also possible, and appear frequently in thefigures as approaches to augmenting the accelerometer/crystal data. Eachof these motion detecting techniques may be the sole motion detectingmodality, or may be part of a multi-modal approach. Many other uni-modaland multi-modal approaches will be obvious to those skilled in the art,but will be based on the principles herein.

In a system with multiple communicating units, at least one of which hasmotion detection capability, one, some, or all of the units may havemotion detecting capability. This section considers two specific simplearchitectures: (a) that in which only one mobile communications unit hasMDC; and (b) that in which all mobile communication units have MDC. Thegeneral case—in which any unit may or may not have MDC—is discussed inthe next section. FIG. 19B schematically depicts these three cases. Theleft-most column depicts a system in which only the IMD has MDC.

Referring to the case of the left-most column in FIG. 19B: Since thedetection of activity by the IMD does not give enough information todetermine whether only the IMD-owner is moving, or whether more upstreamunits such as the CPD are also moving, a simple approach is to increasethe assiduousness of communications between all mobile units upon thedetection of motion by the IMD. For example, any one or more of thetechniques a)-f) listed in (2) above could accomplish this task. Anotherapproach would be: Upon detection of motion by the IMD, use GPS and/orsignal strength data to attempt to learn more about the location of theupstream activity frontier. If the most upstream moving unit is therebydetermined, then the increase in communications assiduousness can berestricted to the pair of units that are (i) the most upstream movingunit and (ii) the next most upstream unit (which will be stationary).

Architecture in which all Movable Units have MDC

FIGS. 20-22 show an example of a system in which all movablecommunication units have MDC; FIG. 20 shows the IMD, FIG. 21 shows arepeater unit and FIG. 22 shows the “final” repeater unit, i.e. the onewhich communicates with a stationary unit (which may itself be arepeater/relay unit or may be the central station). FIG. 23 shows astationary unit which communicates with any of the units shown in FIGS.20-22.

In FIG. 20 and the figures which follow, boxes defined by broken linesindicate an inference drawn based on obtained activity information; Thebroken-line-boxes are intended to indicated the rationale for theoperations which follow them.

The essential feature of FIG. 20 is the determination of which of fouractivity states the system (comprising the IMD and the next upstreamcommunications unit) is in, v.i.z.:

-   -   State #1: IMD active, and next upstream unit active

[Conclusion: The IMD is not the upstream activity frontier, in whichcase communications are left unaltered, as per (4) and (5) among theGeneral Principles above];

-   -   State #2: IMD active, next upstream unit inactive

[Conclusion: The IMD is the upstream activity frontier, in which casedownstream to upstream communication efforts from the IMD to theupstream repeater may be increased, as per (2) and (3) among the GeneralPrinciples above];

-   -   State #3: IMD inactive, next upstream unit active

[Conclusion: The upstream unit is the downstream activity frontier, inwhich case communications efforts from the IMD to the upstream repeatermay be increased, as per (2) and (3) among the General Principlesabove];

-   -   State #4: IMD inactive, next upstream unit inactive [Conclusion:        Probable quiescent state, in which case communications efforts        from the IMD to the upstream repeater may be decreased, as        per (6) and (7) among the General Principles above];

The activity state of the IMD is signaled upstream. Embodiments of theinvention with a greater or lesser number of options for eachcontingency are possible.

FIG. 21, shows the repeater unit algorithm for a system in which allunits have MDC. Since the repeater unit will have both a downstream andan upstream neighbor, eight States are shown, (i) four for the repeaterand its upstream neighbor—which are essentially identical to the fourstates hereinabove for the IMD and its upstream neighbor; and (ii) fourfor the repeater and its downstream neighbor—which are also essentiallyidentical to the four states hereinabove for the IMD and its upstreamneighbor.

In addition to the features which parallel those of FIG. 20, FIG. 21shows the following features:

-   -   If the unit activity status differs from each of its neighbors,        then there is a possibility that the unit is lost or        misplaced—as per (9) among the General Principles above—and four        basic remedial actions are indicated in the figure;    -   If the activity status of three consecutive units is        negative—i.e. all three are not moving, then the level of        certainty of a quiescent state [designated as “probable”] is        greater than the level of certainty if only two consecutive        units are non-moving [in which case the designation is        “possible”]. The distinction between “possible” and “probable”        may be used for decision making in terms of (i) whether to        decrease the assiduousness of communication between the involved        units, and (ii) if there is to be such a decrease, the extent of        the decrease.

FIG. 22 shows an operating algorithm for a “final repeater unit,” i.e. aunit whose downstream neighbor is either the IMD or another repeaterunit, and whose upstream neighbor is a stationary unit. This figure isessentially a simplified version of FIG. 21 in that:

a) It shows the same four States and possible actions for communicatingwith its downstream neighbor;

b) It shows two states and possible actions for communicating with theSU (only two states [v.i.z. (i) final repeater moving, and (ii) finalrepeater not moving], since the SU by definition cannot be in motion);and

c) Since there is no opportunity to compare three consecutive movingunits, the additional features of the general repeater [(i)lost/misplaced detection, and (ii) assessment of level of certainty ofquiescent state] are not present.

Architecture for a General System

FIG. 23 shows an operating algorithm for a stationary unit, defined asthe communications unit which communicates with the most upstream of themobile repeater units (or, if there are no mobile repeater units, withthe IMD itself). In a system in which all downstream units have MDC(e.g. as shown in FIGS. 20-22), the SU would receive either a positiveactivity signal or a negative activity signal from the next downstreamunit. In the case of a positive activity signal, by definition, theupstream activity frontier must be the next downstream unit (since, bydefinition, the SU is not moving), and therefore the listed option T1-T9address this circumstance. Options T1-T5 are the same as those shown inFIGS. 21 and 22 for a non moving upstream unit and an adjacent movingdownstream unit. Options T6 and T7 allow for an examination of otherdeterminants of unit motion (i.e. GPS or signal strength) beforeselecting among T2-T5; The examination of GPS and signal strength couldbe similarly incorporated into the option list of any of the algorithmshereinabove and hereinbelow. T8 is a lateral notification (from one SUto one or more other SUs): It may be used in a structure with multipleSUs (e.g. the upper floor SU telling a lower floor SU that the IMD owneris moving about, perhaps resulting, for example, in an increase inassiduousness of communication by the lower floor SU). T9 allows for thenotification of any downstream units which may not have received thepositive activity signal from the unit immediately downstream from theSU (either because [i] the algorithm may have called for repeater unitsto notify only the next downstream unit; and/or [ii] because the likelynon-battery dependence of the SU allows for more generous use of powerfor transmission purposes).

In the case of a negative activity signal received from the downstreamneighbor, a possibly quiescent state (of motion) exists, and the listedoptions R1-R10 address this circumstance. Options R1-R4 and R10 are thesame as those shown in FIGS. 21 and 22 for a non moving upstream unitand an adjacent non-moving downstream unit. Option R5 allows forswitching to a lower priority or quality communicationchannel/mode/route, if desirable. Options R6 and R7 allow for anexamination of other determinants of unit motion (i.e. GPS or signalstrength) before selecting among R2-R5. The purpose of each of R8 and R9has the same conceptual basis as that of each of T8 and T9 respectively.

One aspect of FIG. 23 which differs from that of FIGS. 20 to 22 is thatthe FIG. 23 algorithm can accommodate a downstream unit which does nothave MDC. In such a circumstance, there is no activity signal from thecommunications unit which is immediately downstream, and there istherefore no adjustment to be made of the SU communications. Algorithmsare possible which, in the event that the immediately downstream unitprovides no activity signal, look further downstream for such a signal.

FIGS. 24-26 parallel FIGS. 20-22 (IMD, repeater unit, final repeaterunit); but FIGS. 24-26 allow for the possibility that a neighboring unitdoes not have motion detecting capability.

FIG. 24, is an algorithm for an IMD with MDC, which allows for operationwith an upstream unit which either does or does not have MDC (whereasFIG. 20 is an algorithm for an IMD with MDC, which allows for operationonly with an upstream unit which has MDC). Accordingly, additionaloptions in FIG. 24 (compared to FIG. 20) address the case of no activitysignal from the upstream neighboring unit, and these are discussedpresently:

Referring to FIG. 24A, if the IMD is moving, and if the activity statusof the next upstream unit is not provided by a MD/A/P in that unit, thenoptions include:

-   -   a) looking further upstream than the adjacent unit; FIG. 24B        shows an algorithm which looks at the two next upstream units        (designated U+2 and U+3) beyond the unit which is adjacent to        the IMD (designated U+1). If the information is obtained from        U+2, then U+3 is not examined; If the information is not        obtained from U+2, then U+3 is examined. Implicit in the        algorithm is the concept that the motion state of unit U+1 is        likely to be the same as that of U+2, and that the motion of U+2        is likely to be the same as that of U+3. Thus if the IMD is        moving, and if the motion status of U+1 is unknown, but U+2 (or,        if necessary, U+3) is known to be moving, then the conclusion is        that the IMD is not likely to be the upstream activity frontier.        On the other hand, if the IMD is moving, and if the motion        status of U+1 is unknown, but U+2 (or, if necessary, U+3) is        known not to be moving, then the conclusion is that the IMD may        be the upstream activity frontier. In each case, conclusions        based on U+2 are more reliable than those based on U+3. Clearly,        it would be possible to allow the system to look even further        upstream, i.e. at U+4, etc., which would be desirable, as shown        in FIG. 24B, if neither of unit U+2 nor unit U+3 had MDC;    -   b) [again referring to FIG. 24A] looking at GPS or signal        quality information to try to determine the motion status of the        IMD with respect to unit U+1. Note that FIG. 24B also calls for        the possible consideration of GPS and/or signal quality        information, if MD/A/P data from U+2 and beyond is insufficient        for a decision;    -   c) [again referring to FIG. 24A] simply making the assumption        that the IMD is the upstream activity frontier (i.e. “err” on        the side of more robust communications), and selecting one of        the options led to from Circle N, which increase the        assiduousness of upstream communications from the IMD; This        approach is also indicated as an option in FIG. 24B, in the        event that neither of U+2 nor U+3 offers MD/A/P information;        and/or    -   d) taking no action.

The other difference between FIG. 24 and FIG. 20 is the inclusion inFIG. 24 of a set of options for the combination of no IMD motion and noMD/A/P signal from the next upstream communications unit. The optionsare conceptually parallel to those immediately above for the case of IMDmotion and no MDC in the upstream unit.

Referring again to FIG. 24A, if the IMD is not moving, and if theactivity status of the next upstream unit is not provided by a MD/A/P inthat unit, then options include:

-   -   a) looking further upstream than the adjacent unit; FIG. 24C        shows an algorithm which looks at the two next upstream units        (U+2 and U+3) beyond the unit which is adjacent to the IMD        (U+1). If the information is obtained from U+2, then U+3 is not        examined; If the information is not obtained from U+2, then U+3        is examined. As was the case with FIG. 24B, implicit in the        algorithm is the concept that the motion state of unit U+1 is        likely to be the same as that of U+2, and that the motion of U+2        is likely to be the same as that of U+3. Thus if the IMD is not        moving, and if the motion status of U+1 is unknown, but U+2 (or,        if necessary, U+3) is known to be moving, then the conclusion is        that unit U+1 may be the downstream activity frontier, and        options include efforts to increase the assiduousness of        communications between U and U+1. On the other hand, if the IMD        is not moving, and if the motion status of U+1 is unknown, but        U+2 (or, if necessary, U+3) is known not to be moving, then the        conclusion is that there may be an overall quiescent state, and        options to decrease the assiduousness of communications between        U and U+1 may be undertaken. As was the case with FIG. 24B, (i)        in each case, conclusions based on U+2 are more reliable than        those based on U+3; and (ii) clearly, it would be possible to        allow the system to look even further upstream, i.e. at U+4,        etc., which would be desirable, as shown in FIG. 24C, if neither        of unit U+2 nor unit U+3 had MDC;    -   b) [again referring to FIG. 24A] looking at GPS or signal        quality information to try to determine the motion status of the        IMD with respect to unit U+1. Note that FIG. 24C also calls for        the possible consideration of GPS and/or signal quality        information, if MD/A/P data from U+2 and beyond is insufficient        for a decision;    -   c) [again referring to FIG. 24A] simply making the assumption        that the lack of IMD motion is part of an overall quiescent        state, and therefore selecting one of the options led to from        Circle Q, which decrease the assiduousness of upstream        communications from the IMD; This approach is also indicated as        an option in FIG. 24C, in the event that neither of U+2 nor U+3        offers MD/A/P information; and/or    -   d) taking no action.

FIG. 25, is an algorithm for a repeater unit with MDC, which allows foroperation with (i) an upstream unit which either does or does not haveMDC (whereas FIG. 21 is an algorithm for a repeater unit with MDC, whichallows for operation only with an upstream unit which has MDC); and (ii)a downstream unit which either does or does not have MDC (whereas FIG.21 is an algorithm for a repeater unit with MDC, which allows foroperation only with a downstream unit which has MDC).

Accordingly, four additional sets of options in FIG. 25 (compared toFIG. 21) address the case of no activity signal from the neighboringunits, and these are discussed hereinbelow. The four sets of options arefor:

-   -   Case 1: repeater unit in motion, no upstream activity signal        from MD/A/P;        -   Case 2: repeater unit in motion, no downstream activity            signal from MD/A/P;        -   Case 3: repeater unit in not in motion, no upstream activity            signal from MD/A/P; and        -   Case 4: repeater unit in not in motion, no downstream            activity signal from MD/A/P.

Regarding Case 1 (immediately above): Referring to FIG. 25A, if therepeater unit is moving, and if the activity status of the next upstreamunit is not provided by a MD/A/P in that unit, then the managementoptions are conceptually parallel to those enumerated in the case of theIMD with repeater unit indicating motion and with upstream unit nothaving MD/A/P (FIG. 24), including:

-   -   a) looking further upstream than the adjacent unit; FIG. 25D        shows an algorithm which looks at the two next upstream units        (U+2 and U+3) beyond the unit which is next upstream from the        repeater (U+1). The algorithm is conceptually identical to that        shown in FIG. 24B: If the information is obtained from U+2, then        U+3 is not examined; If the information is not obtained from        U+2, then U+3 is examined; If the information is not obtained        from either U+2 or U+3, looking further upstream is a        possibility;    -   b) [again referring to FIG. 25A] looking at GPS or signal        quality information to try to determine the motion status of the        repeater unit with respect to unit U+1. Note that FIG. 25D also        calls for the possible consideration of GPS and/or signal        quality information, if MD/A/P data from U+2 and beyond is        insufficient for a decision;    -   c) [again referring to FIG. 25A] simply making the assumption        that the repeater unit is the upstream activity frontier, and        selecting one of the options led to from Circle E, which        increase the assiduousness of upstream communications from the        repeater unit; This approach is also indicated as an option in        FIG. 25D, in the event that neither of U+2 nor U+3 offers MD/A/P        information; and/or    -   d) taking no action.

Regarding Case 2: Referring to FIG. 25A, if the IMD is moving, and ifthe activity status of the next downstream unit is not provided by aMD/A/P in that unit, then options are conceptually parallel to thoseenumerated in Case 1, including:

-   -   a) looking further downstream than the adjacent unit; FIG. 25C        shows an algorithm which looks at the two next downstream units        (designated U−2 and U−3) beyond the unit which is adjacent to        the repeater unit (designated U−1). If the information is        obtained from U−2, then U−3 is not examined; If the information        is not obtained from U−2, then U−3 is examined. Implicit in the        algorithm is the concept that the motion state of unit U−1 is        likely to be the same as that of U−2, and that the motion of U−2        is likely to be the same as that of U−3. Thus if the repeater is        moving, and if the motion status of U−1 is unknown, but U−2 (or,        if necessary, U−3) is known to be moving, then the conclusion is        that the repeater unit is not likely to be the downstream        activity frontier. On the other hand, if the repeater unit is        moving, and if the motion status of U−1 is unknown, but U−2 (or,        if necessary, U−3) is known not to be moving, then the        conclusion is that the repeater unit may be the downstream        activity frontier. In each case, conclusions based on U−2 are        more reliable than those based on U−3. Clearly, it would be        possible to allow the system to look even further downstream,        i.e. at U−4, etc., which would be desirable, as shown in FIG.        25C, if neither of unit U−2 nor unit U−3 had MDC;    -   b) [again referring to FIG. 25A] looking at GPS or signal        quality information to try to determine the motion status of the        repeater unit with respect to unit U−1. Note that FIG. 25C also        calls for the possible consideration of GPS and/or signal        quality information, if MD/A/P data from U−2 and beyond is        insufficient for a decision;    -   c) [again referring to FIG. 25A] simply making the assumption        that the repeater unit is the downstream activity frontier (i.e.        “err” on the side of more robust communications), and selecting        one of the options led to from Circle C, which increase the        assiduousness of downstream communications from the repeater        unit; This approach is also indicated as an option in FIG. 25C,        in the event that neither of U−2 nor U−3 offers MD/A/P        information; and/or    -   d) taking no action.

Regarding Case 3 (hereinabove): Referring to FIG. 25B, if the repeaterunit is not moving, and if the activity status of the next upstream unitis not provided by a MD/A/P in that unit, then the management optionsare conceptually parallel to those enumerated in the case of the IMDwith repeater unit indicating no motion and with upstream unit nothaving MD/A/P (FIG. 24), including:

-   -   a) looking further upstream than the adjacent unit; FIG. 25F        shows an algorithm which looks at the two next upstream units        (U+2 and U+3) beyond the unit which is next upstream from the        repeater (U+1). The algorithm is conceptually identical to that        shown in FIG. 24C: If the information is obtained from U+2, then        U+3 is not examined; If the information is not obtained from        U+2, then U+3 is examined; If the information is not obtained        from either U+2 or U+3, then looking further upstream is a        possible option;    -   b) [again referring to FIG. 25B] looking at GPS or signal        quality information to try to determine the motion status of the        repeater unit with respect to unit U+1. Note that FIG. 25F also        calls for the possible consideration of GPS and/or signal        quality information, if MD/A/P data from U+2 and beyond is        insufficient for a decision;    -   c) [again referring to FIG. 25B] simply making the assumption        that the repeater unit is part of a local quiescent state, and        selecting one of the options led to from Circle L, which        decrease the assiduousness of upstream communications from the        repeater unit; This approach is also indicated as an option in        FIG. 25F, in the event that neither of U+2 nor U+3 offers MD/A/P        information; and/or    -   d) taking no action.

Regarding Case 4 (hereinabove): Referring to FIG. 25B, if the repeaterunit is not moving, and if the activity status of the next downstreamunit is not provided by a MD/A/P in that unit, then the managementoptions are conceptually parallel to those enumerated in Case 3,including:

-   -   a) looking further downstream than the adjacent unit; FIG. 25E        shows an algorithm which looks at the two next downstream units        (U−2 and U−3) beyond the unit which is next upstream from the        repeater (U−1). If the information is obtained from U−2, then        U−3 is not examined; If the information is not obtained from        U−2, then U−3 is examined; If the information is not obtained        from either U−2 or U−3, then looking further downstream is a        possible option;    -   b) [again referring to FIG. 25B] looking at GPS or signal        quality information to try to determine the motion status of the        repeater unit with respect to unit U−1. Note that FIG. 25E also        calls for the possible consideration of GPS and/or signal        quality information, if MD/A/P data from U−2 and beyond is        insufficient for a decision;    -   c) [again referring to FIG. 25B] simply making the assumption        that the repeater unit is part of a local quiescent state, and        selecting one of the options led to from Circle H, which        decrease the assiduousness of downstream communications from the        repeater unit; This approach is also indicated as an option in        FIG. 25E, in the event that neither of U−2 nor U−3 offers MD/A/P        information; and/or    -   d) taking no action.

As was the case with FIG. 21 (repeater unit for system in which allunits have MDC), the repeater unit algorithm shown in FIG. 25 alsoallows for:

-   -   a) the detection of a lost or misplace unit; and    -   b) an increased level of certain about a the existence of a        quiescent state when three consecutive units are each in a        non-motion state.

FIG. 26, is an algorithm for a final repeater unit with MDC, whichallows for operation with a downstream unit which either does or doesnot have MDC (whereas FIG. 22 is an algorithm for a final repeater unitwith MDC, which allows for operation only with a downstream unit whichhas MDC). The algorithm is essentially the same as that of FIG. 25 forthe general repeater, except that all upstream communications areunderstood to be with a unit that is in a non-motion state. Thiseliminates upstream communication considerations related to either (i) amoving upstream unit or (ii) an upstream unit whose motion status isuncertain. (Also, option 5 of the list of options led to by Circle L inFIG. 25B is eliminated in FIG. 26B, since it calls for additionalevaluation by looking at the motion state further upstream.)

To complete the possible configurations of a mixed system, whichincludes both (i) mobile communicating units with and (ii) mobilecommunicating units without MDC, algorithms are presented for each of anIMD, a repeater unit and a final repeater unit which do not have MDC butwhich operate with one or more adjacent units which do have MDC.

FIG. 27A shows an IMD which does not have MDC, but which may receive andrespond to signals derived from MD/A/P apparatus in its adjacentupstream neighbor. If the upstream unit shows no activity, then thelisted options M1-M7 include (i) a decrease in the assiduousness ofupstream communications, based on the assumption of a locally quiescentstate; (ii) further evaluation based on an examination of either GPS orsignal quality data; or (iii) no change in communication management. Analgorithm which does not decrease the assiduousness of upstreamcommunication in the event of a negative activity signal from upstreamis possible, since in that circumstance, the IMD could be the upstreamactivity frontier.

If the upstream unit shows activity, then the listed options N1-N7include (i) an increase in the assiduousness of upstream communications,based on the assumption that one can't rule out the next upstream unitbeing the downstream activity frontier; (ii) further evaluation based onan examination of either GPS or signal quality data; or (iii) no changein communication management. No signal from upstream calls for noaction. An algorithm which does not increase the assiduousness ofupstream communication in the event of a positive activity signal fromupstream is possible, since in that circumstance, the IMD could bemoving with the upstream unit. Algorithms which look further upstreamthan the adjacent communications unit (no matter which signal isreceived from that adjacent unit) are possible.

FIG. 27B shows a repeater unit without MDC which may receive and respondto signals derived from MD/A/P apparatus in (i) its adjacent upstreamneighbor, and (ii) its adjacent downstream neighbor. Responses K1-K7 tonegative activity signals from an upstream unit are the same as thosefor the IMD without MDC (M1-M7). In addition, in the case of therepeater herein, if a positive activity signal is received fromdownstream, then consideration is given to the possibility that therepeater herein could be in a positive activity state, making it theupstream activity frontier; In such a circumstance, options whichincrease the activity of upstream communications are desirable (L2-L5).

Responses L1-L7 to positive activity signals from an upstream unit arethe same as those for the IMD without MDC (N1-N7). In addition, in thecase of the repeater herein, if a positive activity signal is receivedfrom downstream, then consideration is given to the possibility that therepeater herein could be in a positive activity state, implying thepossibility that all three adjacent units are moving together; In such acircumstance, there would be no need to increase the assiduousness ofupstream communications.

If there is no signal from the upstream communications unit, thealgorithm calls for no communication modification at the repeater unitdescribed herein.

The response of the repeater unit without MDC to downstream activityinformation is conceptually parallel to its response to upstreamactivity information. A negative downstream activity signal leads tooptions H1-H7, which parallel options K1-K7 (except that the repetitionrate of S1s is the subject of H4, while the repetition rate of S2s isthe subject of K4). In addition, in the case of the repeater herein, ifa positive activity signal is received from upstream, then considerationis given to the possibility that the repeater herein could be in apositive activity state, making it the downstream activity frontier; Insuch a circumstance, options which increase the activity of downstreamcommunications are desirable (J2-J5). A positive downstream activitysignal leads to options J147, which parallel options L1-L7 (except thatthe repetition rate of S1s is the subject of J4, while the repetitionrate of S2s is the subject of L4). In addition, in the case of therepeater herein, if a positive activity signal is received fromupstream, then consideration is given to the possibility that therepeater herein could be in a positive activity state, implying thepossibility that all three adjacent units are moving together; In such acircumstance, there would be no need to increase the assiduousness ofdownstream communications. Finally, if there is no signal from thedownstream communications unit, the algorithm calls for no communicationmodification at the repeater unit described herein.

FIG. 27C shows an operating algorithm for a final repeater unit (i.e.the repeater which communicates with the SU) which does not have MDC.Because, by definition, the state of motion of the next upstreamcommunications unit is known to be stationary, the algorithm omits (i)all of the response options to upstream activity signals shown in FIG.27B; and (ii) options analogous to H8 and J8 of FIG. 27B [since theyalso concern upstream motion]. Thus options P1-P7 parallel optionsH1-H7, and options Q1-Q7 parallel options J147.

FIGS. 20-27C initially consider only the information from accelerometeror piezoelectric motion detecting apparatus, and consider GPS and/orsignal quality information on a secondary basis. FIGS. 12 and 13consider GPS and signal quality without blending in MD/A/P information.However, algorithms for position, motion and acceleration analysis maybe based other ways of “blending” the information from (i) MD/A/Pinformation, (ii) GPS information and (iii) signal quality information,e.g.

-   -   considering GPS as the primary data (e.g. in an algorithm        similar to that shown in FIGS. 20-27C, and in which, optionally,        one or more of MD/A/P information and signal quality information        are secondary considerations);    -   considering signal quality is used as the primary data, with one        or more of MD/A/P and GPS as secondary information;    -   consider a blend of any two modalities as the primary data (e.g.        [i] define a positive motion state if either of GPS or MD/A/P        indicates activity, or [ii] define a positive motion state if        both GPS and MD/A/P indicate activity);    -   consider a blend of all three as the primary data (e.g. [i]        define a positive motion state if any of GPS or signal quality        or MD/A/P indicates activity, or [ii] define a positive motion        state if any two out of three of GPS, signal quality and MD/A/P        indicate activity, or [iii] define a positive motion state if        all of GPS, signal quality and MD/A/P indicate activity, or [iv]        define a positive motion state if signal quality and either of        GPS or MD/A/P indicate activity, etc.)

Still other ways of blending the information will be apparent to thoseskilled in the art.

Even more complex algorithms result from the consideration of GeneralPrinciple 12 hereinabove, i.e. that activity may be considered in a more“fine grained” manner than simply all or none. For example, a five stateformat could include (i) negative, (ii) weakly positive, (iii)intermediate positive, (iv) strongly positive, and (v) unknown. Amultistate format (involving the same, a lesser number or a greaternumber of states) could be used for one or more of MD/A/P, GPS andsignal quality information in a blended format.

In these systems with augmented motion detection capabilities, the basicgoals are the same as those defined hereinabove, i.e. the use of motioninformation to optimize signal quality and battery drainage, each inboth real time, and proactively.

The approach hereinabove general concerns tandem communication unitswith a “series” structure, i.e. unit U sends IMD information to unitU+1, which relays the information to unit U+2, etc. However, parallelcommunication elements, as illustrated in FIG. 28, can increase thereliability of the system. FIG. 28 shows a network structure in whichunit U communicates with unit U+2 via (i) unit U+1A, (ii) unit U+1B,(iii) unit U+1A followed by unit U+1B, or (iv) unit U+1B followed byunit U+1A. With this architecture, the loss of any one communicationslink will not prevent U and U+2 from communicating, and someconfigurations with up to three non-functioning links will still allow Uand U+2 to communicate.

For example, if both of (i) the link between U and U+1A, and (ii) thelink between U+1B and U+2 are non-functioning, then U can communicatewith U+2 via the route U←→U+1B←→U+1A←→U+2. U could either sendinformation to both U+1A and U+1B, or, if U was provided with theinformation that the best route is U←→U+1B←→U+1A←→U+2, then U could sendinformation only to U+1B. All of the aforementioned potentially appliesin the reverse direction—i.e. U+2 sending information to U, but it isnot necessarily a given that the optimum U+2 to U route is simply theinverse of the U to U+2 route, because an upstream transmitter may havedifferent power output than a downstream one, because receivercharacteristics may differ, and because of different transmissionchannels.

An example of the communication elements which may form the networkshown in FIG. 28 is:

-   -   Unit U=IMD    -   Unit U+1A=WD    -   Unit U+1B=CPD    -   Unit U+2=SU

FIG. 29A shows a more complex arrangement than that of FIG. 28. Althoughthere are only two more communication repeater units, there are manymore communication links (14 vs. 5) and a much larger number of routesbetween the first and the last unit (40 {[4×3×2]+[4×3]+4} vs. 4). Withthis architecture, the loss of any three communications links will notprevent U and U+3 from communicating, and some configurations with up to11 non-functioning links will still allow units U and U+3 tocommunicate.

One feature which increases the number of possible system paths in FIG.28, compared to 29, is allowing for not only “lateral” communication(e.g. unit U+1A and unit U+1B may communicate), but also allowing for“backward communication,” (e.g. unit U communicates with unit U+3 viathe path U←→U+2A←→U+1B←→U+3). This could occur because the repeaterunits are not arrayed geometrically in the pattern shown in the figure.In the previous example, the unit U is ordinarily expected to be nearerto unit U+1A than to U+2A, unit U+1A may have become misplaced orinoperative; the same may (misplacement or inoperative state) may betrue of unit U+2B, hence the aforementioned choice of route.

An example of the communication elements which may form the networkshown in FIG. 29A is:

-   -   Unit U=IMD    -   Unit U+1A=WD    -   Unit U+1B=CPD    -   Unit U+2A=SU#1    -   Unit U+2B=SU#2    -   Unit U+3=CS.

(In this case, it would be unlikely that one SU would send IMDinformation to the other or to a downstream location on the way to theCS.)

In another example, unit U is the IMD; while high capability RFIDs couldconstitute units U+1A and U+1B; unit U+2A could be a WD; unit U+2B couldbe a CPD; and unit U+3 a SU. In yet another example, the IMD is unit U;different types of WD (one on a wrist and one embedded in clothing)could constitute units U+1A and U+1B; units U+2A and U+2B could be twodifferent CPDs; and unit U+3 a SU.

As indicated for the case of the configuration shown in FIG. 28, theunits at each end of the network (the IMD and the CS) could sendinformation to each possible neighboring unit, which could then continuesending information to each possible neighbor, ultimately resulting indissemination of the information to all elements of the network.Alternatively, if the status of each communication link of the networkis available to the CS and the IMD, then only the necessary repeaterunits would be sent the information. Since there are 14 two way links,there are 28 sets of data that indicate the quality of each of theselinks.

FIG. 29B illustrates an array of such information. The letter in eachcell indicates the communication conditions from the unit labeled in theleft-most column to the unit labeled in the top row. Thus C indicatesthe communication conditions from unit U+1A to unit U (e.g. the qualityof a S1 received by sent by unit U+1A and received by unit U), while C*(which is not necessarily the same as C) indicates the communicationconditions from unit U to unit U+1A (e.g. the quality of a S2 receivedby sent by unit U and received by unit U+1A). The blank boxes indicateunits which do not communicate (i.e. each unit with itself, and theunits at the far ends [in this case units U and U+3]). C could be anumber (e.g. representing signal quality), or could be an array ofnumbers (e.g. each element in the array indicating [i] the communicationconditions on each of a number of possible frequencies, [ii] thecommunication conditions using a number of different communicationmodalities, [iii] an evaluation of the error rate for data transmission,[iv] other communication parameters, or [v] combinations of [i] to[iv]). Though the composite communication status information “CCSI” ispresented as a matrix in FIG. 29B, it could simply be stored as one filewith 28 numbers (or a multiple of 28 numbers), or 28 files, or in any ofa variety of ways that will be obvious to those skilled in the art.

The CCSI can be stored in one of the communication units designated asthe master unit; For example, each communication element could pass itsinformation to the CS or the SU. Alternatively the information obtainedat each unit could be passed along to its neighbors, so that it isultimately disseminated over the entire network, resulting in eachmember of the network having access to the CCSI.

The number of columns in FIG. 29B, as well as the number of rows can bea greater or lesser number. The array can be two dimensional, onedimensional (i.e. a string of data with pre-defined demarcations), orhave dimension number greater than two (e.g. if each cell in the matrixconsists of data that can be arrayed multi-dimensionally. Theoverarching issue is that communication decisions may be made by storingnetwork-wide communication conditions in one or more locations. It wouldalso be possible to store communication conditions for only a localarea; For example, the CPD could store information concerning allpossible links downstream from it.

In one embodiment of the invention, a communications unit which storesall system-wide or all local communication information could be endowedwith heuristic software so that, over a period of time, it learnscertain patterns of activity of the IMD-owner which impactcommunications, and makes adjustments accordingly. This could involveturning down handshaking and position-confirming efforts during the IMDowner's sleep period (which could be determined by motion detectingapparatus in the IMD or in any device worn by or implanted in the IMDowner). Another example: On a certain night each week, the IMD ownergoes bowling in a basement level area, or attends meetings in a basementlevel conference room. Communication adjustments could then be made inadvance. It might be possible, for example, to strategically place theCPD so that it can adequately perform a repeater function with the IMDowner at the basement level. Alternatively, it might call for theinstallation of an SU at that location (either temporarily orpermanently), which could directly access both (i) a telephone networkor the internet, and (ii) an IMD owner communication device such as aCPD or WD.

FIG. 30 shows the variety of signals which may enter a downstreamcommunication unit. These include:

-   -   a) a routine S1 handshake signal from an upstream communications        unit;    -   b) a signal indicating that the upstream communications unit is        not receiving this unit's S2: “S2 not received” signal    -   c) one or more types of signal requesting an increase in power        output (coming from either an upstream or a downstream        communications unit, because that respective unit is either not        receiving an expected handshake signal or is receiving a        suboptimal quality signal);    -   d) one or more types of signal requesting an increase in        sensitivity of this unit's receiving apparatus (coming from        either an upstream or a downstream communications unit, because        that respective unit is either not receiving an expected        handshake signal or is receiving a signal from this unit        indicating receipt of suboptimal quality signals at this unit,        or indicating absent [but expected signals] at this unit);    -   e) signals indicating that a high quality signal has been        received at either the upstream or the downstream unit;    -   f) signals requesting user notification (These would be for a        device which has such capability, e.g. a suitably configured SU,        CPD, or WD);    -   g) signals carrying GPS information from either an upstream or a        downstream unit;    -   h) signals carrying motion information from either an upstream        or a downstream unit;    -   i) signals indicating decreased battery voltage in either an        upstream or a downstream unit;    -   j) a routine S2 handshake signal from a downstream communication        unit;    -   k) a signal indicating that the downstream communications unit        is not receiving this unit's S1: “S1 not received” signal;    -   l) a signal representing the CCSI described hereinabove; and    -   m) a signal which causes a notification device to indicate to an        IMD owner that his consent is requested for the        acceptance/installation of an instruction/program for the IMD        from the CS.

FIG. 31A, 31B and 32 show apparatus and methods for transmittinginstructions from the CS to the IMD such that the sender can be certainthat the instruction was received in non-corrupted form. Hereinabove andhereinbelow, “instruction” includes a software computer program, aprogram update or modification, a command or any signal which controlsthe functioning of the IMD.

The crux of these figures is that a copy of the instruction receiveddownstream is transmitted upstream back to the sending source forcomparison with the initially sent instruction. If the returned copy isthe same as the initially transmitted one, it can be assumed that theinstruction arrived at the point from which return occurred inun-corrupted form.

As shown in FIG. 31A (the downstream transmission) and FIG. 31B (theupstream return), the instruction may be

-   -   A) transmitted all the way from the CS/MD [central station and        or medical doctor {i.e. a physician who desires to provide an        instruction}] to the IMD, stored in a buffer memory, and then        returned to the CS/MD, or        -   1) If the comparison indicates and uncorrupted transmission,            the transmission task is complete and the instruction may be            installed, enacted, etc.        -   2) If the comparison indicates a corrupted transmission            -   a) if one or more relay units were used in the                transmission, request a return of one or more of those                relay's memory, to attempt to determine the point of                corruption; Once the point is identified, attempt to                bypass that point in the transmission process;            -   b) if no relays were used, retransmit using one or more                relays; or    -   B) transmitted only a portion of the route from CS/MD to the        IMD, e.g. from the CS/MD to Relay Unit #1, and then returned to        the CS/MD for comparison.        -   1) If the comparison indicates an un-corrupted transmission,            options are        -   a) transmit the instruction from the memory of relay unit #1            to the next downstream unit (in the case shown in the            figure, Relay Unit #2), then retransmit from Relay #2 to            Relay #1 to confirm faithful transmission; Continue stepwise            transmissions until the instruction reaches the IMD in            un-corrupted form; or        -   b) transmit the instruction from the CS/MD to the next            downstream unit (in the case shown in the figure, Relay Unit            #2), then retransmit from Relay #2 to CS/MD to confirm            faithful transmission; Continue stepwise transmissions until            the instruction reaches the IMD in un-corrupted form;    -   2) If any comparison indicates a corrupted transmission, attempt        to bypass the unit responsible involved in the corrupted step.        For example, if the return transmission from Relay Unit #1, when        assessed at the CS/MD, does not match the initial instruction,        attempt to bypass the potentially problematic unit; In this        exemplary case, that would involve an attempted transmission        from CS/MD to Relay Unit #2 directly (i.e. not via Relay Unit        #1), or an attempted transmission from CS/MD to IMD.    -   FIG. 32 shows an algorithm for comparing the initial instruction        sent downstream with its corresponding copy sent upstream for        confirmation. Two approaches are shown:    -   a) one in which the copy is automatically sent upstream, upon        receipt of a new instruction, and    -   b) one in which the upstream reflected copy of the instruction        is only sent if, after receiving a signal that the instruction        was received downstream, the upstream unit requests the copy.    -   Options if the upstream unit determines that the copy that it        has received is correct include:        -   a) if it is confirmed that the proper instruction has            arrived at the IMD, instructing the            -   IMD to install/enact the instruction;        -   b) commanding the downstream unit which has properly            received the instruction to            -   forward the instruction on to the next downstream unit;                and        -   c) sending an additional instruction.    -   Options if the upstream unit determines that the copy that it        has received is not correct include:    -   a) notifying the system administrator;    -   b) command the downstream unit to delete the previous        instruction from its memory, and then re-transmit the        instruction; and    -   c) command the downstream unit to delete the corrupted segment        of the previous instruction from its memory, and then        re-transmit that segment.

Although the aforementioned discussion pertains to the verification ofinstructions transmitted downstream, it could also be used to verify theproper transmission of information in the upstream direction. Suchupstream information could include a) patient data, b) confirmations ofexecuted commands, and c) device self monitoring data. In the case ofdata, for example, data could be 1) stored in the IMD, 2) transmittedfrom the IMD to the CS; 3) re-transmitted from the CS to the IMD; 4) atthe IMD, the data that was re-transmitted from the CS would be comparedwith the data which was initially transmitted from the IMD.

Other methods and apparatus for confirmation of un-corrupted distantreceipt of a signal set are known in the art.

An alternative way of determining if certain types of instruction wereproperly delivered from the CS to the IMD is a functional evaluation ofthe IMD post instruction delivery. FIG. 33 shows an apparatus and methodfor such a functional evaluation entailing:

-   -   1) the temporary disconnection of the IMD processor input from        the IMD sensors outputs, and the substitution of test signals as        processor inputs; and    -   2) the temporary disconnection of the input to either the IMD        actuator circuits or the disconnection of the input to a more        proximal point in the actuation process (i.e. a point after a        therapy decision is made but before it is executed).

If the IMD is an ICD, examples of actuator circuits are circuits whichsupply the energy for cardiac pacing and defibrillation; and examples ofmore proximal points in the actuation process are circuits whichactivate the aforesaid energy supply circuits.

The test signals would reflect various scenarios that would, followingthe installation/enactment of a new instruction, result in an IMD actionwhich differs from the expected action prior to theinstallation/enactment of the new instruction. Among the instructionswhich could be functionally evaluated are a) reprogramming of alreadyexisting software; and b) new software with different operatingcharacteristics than the previous software, c) an improved softwareversion which does not contain an error which was present in a previousversion, and d) a patch for an already installed software version whichcontained an error.

For example: If the IMD is an ICD, a simple example is reprogramming therate cutoff for detection of VT. Consider an instruction whichreprograms the VT rate cutoff from 190 beats per minute (“BPM”) to 200BPM. The test procedure could involve:

-   -   a) changing the output so that the response to a test signal is        not delivered to the patient; In the case of the ICD, it would        mean that either (i) once VT is detected, neither        anti-tachycardia pacing (“ATP”) nor shock is triggered, or (ii)        ATP or shock is delivered to a dummy load;    -   b) changing the processor input source from the ventricular        sensing lead to the source of electrogram test signals [which        could be a) transmitted from the CS, or b) from an internal test        generator within the ICD];    -   c) supplying the electrogram test signals [e.g. (i) supplying        electrograms which simulate a heart rate of 199 BPM, with        non-detection of VT being the expected response; and (ii)        supplying electrograms which simulate a heart rate of 201 BPM,        with detection of VT being the expected response];    -   d) observing the response to the test signals    -   e) at the completion of the test, changing the processor input        source back to the ventricular sensing lead and restoring output        routing so that ATP or shock is delivered to the patient.

Another example: replacing the electrogram analysis software with a morerobust analysis package. The package could be one which more accuratelydiscriminates between ventricular tachycardia and supraventriculartachycardia. The test procedure could involve: involve:

-   -   a) changing the output so that the response to a test signal is        not delivered to the patient;    -   b) changing the processor input source from the ventricular        sensing lead to the source of electrogram test signals;    -   c) supplying the electrogram test signals (e.g. test signals        designed/selected to determine if the new software properly        distinguishes between VT and SVT);    -   d) observing the response to the test signals    -   e) at the completion of the test, changing the processor input        source back to the ventricular sensing lead and restoring output        routing so that ATP or shock is delivered to the patient.    -   Observing the response to the test signals (and thus determining        if the new instruction resulted in the desired IMD performance)        may involve (a) transmitting a copy or a representation of the        processor output, (b) transmitting a copy or representation of        the input to an actuator circuit, as defined hereinabove; (c)        interrogating the IMD following the test procedure; or (d)        combinations of (a)-(c). By analysis of this copy or        representation, a remote person may determine if the new        instruction    -   a) has been properly received by the IMD; and    -   b) whether the new instruction allows the IMD to function in the        intended manner; and    -   c) whether the new instruction compromises the functioning of        any other IMD tasks (Examples would be (i) new software improves        the sensitivity of VT detection but decreases the specificity of        VT detection in an ICD; and (ii) new software compromises the        functioning of the IMD by impairing the operation of another IMD        program or a segment of another IMD program.)

In a preferred embodiment of the invention, the IMD would be capable ofresponding to a situation requiring the need for immediate therapy, ifsuch situation occurs during the test procedure. This feature may beaccomplished, as is shown in FIG. 34, by having two processors whichoperates in parallel: Processor #2—which does not initially receive thenew instruction, and Processor #1—which does receive the newinstruction. During the testing of Processor #1 after it has receivedthe new instruction, Processor #2 (which runs the old, not the newinstruction) continues to monitor the patient. If Processor #2 indicatesthe need for immediate therapy, then Processor #2 may:

-   -   a) itself directly activate the IMD actuator circuit; or    -   b) restore the input of the IMD actuator circuit to the output        of Processor #1. In this case, it may    -   (i) also switch the input of Processor #1 back to the real time        signals from the IMD lead/sensor, etc.;    -   (ii) provide Processor #1 with a copy of the signal(s) which        triggered the interruption of the test procedure, such signals        having been stored in memory; or    -   (iii) (iii) perform both (i) and (ii).    -   Following the completion of therapy for the event which required        immediate attention, the test procedure is completed. Following        the completion of the test procedure, if it indicates the        updated version of Processor #1 is functioning in a desirable        way, Processor #2 may be updated with the new instruction.    -   For example, if VT requiring therapy occurs during a test of new        VT detection software for Processor #1, the VT is detected by        Processor #2. Processor #2 may then itself directly activate the        IMD actuator, or may cause Processor #1 to evaluate the VT,        after which Processor #1 would determine the response to the VT.    -   The aforementioned IMD test apparatus and methods may also be        used to evaluate IMD performance even if no new instruction was        delivered. This may be done:    -   a) as part of periodic IMD maintenance by the IMD;    -   b) as part of periodic IMD maintenance by a remote source;    -   c) in the event that there is a question (on a non-periodic        basis) about whether the IMD will perform properly, such        question based on:    -   (i) a determination that the aging process [e.g. of the battery,        the sensor(s), etc.] may negatively impact IMD performance;    -   (ii) the IMD manufacturer or other authority having become aware        that certain clinical scenarios do not result in optimum IMD        performance; and/or    -   (iii) other considerations.

IMD Security Issues:

Encryption/Decryption

In order to minimize the chance that an unauthorized person could gainaccess to a patient's IMD, the techniques illustrated in FIGS. 35A to39, and others known in the art may be employed.

FIGS. 35A to 35C illustrate the deployment of an encryption/decryptionkey which may be stored in the IMD and in an approved remote station,which will, at later times be allowed to communicate with the IMD. Thekey is used to encrypt information which is sent from the IMD to theremote station and to decrypt it upon its arrival at the remote station.The same, a similar or an entirely different key may be used to transmitinstructions/commands/programs from the remote station to the IMD. Theremote station may be a central station as is described in U.S. Pat. No.7,277,752, a peripheral station as is described in U.S. patentapplication Ser. No. 11/502,484, a central station which handles avariety of IMDs, a central station which handles both implanted andexternal medical devices, or a physician's office.

The appropriate key is stored in the memory of the remote station and ofthe IMD. The memory may be a write once only type, or a re-writeabletype. As used hereinabove and hereinbelow, the term “key” is intended toinclude systems and methods of encryption at the sending end of acommunication link, and decryption at the receiving end, as well asmethods of password protection.

The key may be generated at the time the device is manufactured. In apreferred embodiment of the invention, the key would be generated at thetime that the device is implanted. Since the identity of either acontrolling physician or central station might then be known, a singlecorresponding key could then be generated and stored in the appropriateremote station. FIG. 35A shows an embodiment of the invention in whichthe encryption/decryption key or keys are generated by a freestandingdevice which is not part of either the IMD or the remote station. Theinformation is entered into the IMD by techniques know in the art. Thecorresponding copy for the remote station a) may be transmitted to theremote station at substantially the same time as it is entered into theIMD, b) may be transmitted to the remote station at a later time, or c)may be stored on a portable memory device, to be transported to theremote station. Embodiments of the invention with one or more additionalcopies of the key are possible. In a preferred embodiment of theinvention, once the appropriate number of key copies is generated, thekey is not stored in the key generator.

FIG. 35B shows an embodiment of the invention in which theencryption/decryption key or keys are generated by circuitry which ispart of the IMD. The corresponding copy for the remote station a) may betransmitted to the remote station at substantially the same time as theIMD is planted, b) may be transmitted to the remote station at a latertime, or c) may be stored on a portable memory device at the time ofdevice implantation or at a later time, to be transported to the remotestation. In the setup shown in FIG. 35B, to restrict access to theencryption/decryption information in the IMD, copying of it may be a)restricted to a once only basis, b) restricted to a specific window intime (e.g. the time of IMD implantation), c) password protected, or d)protected by methods which are combinations of a) through c) listedimmediately hereinabove.

FIG. 35C shows an embodiment of the invention in which theencryption/decryption key or keys are generated by circuitry which ispart of the remote station. The corresponding copy for the IMD a) may betransmitted to the IMD at substantially the same time as the IMD isplanted, b) may be transmitted to the IMD at a later time, or c) may bestored on a portable memory device at the time of its generation at theremote station, to be transported to the IMD for entry either at thetime of IMD implantation or later. In the setup shown in FIG. 35C, torestrict access to the encryption/decryption information in the remotestation, copying of it may be a) restricted to a once only basis, b)restricted to the a specific window in time, c) password protected, ord) protected by methods which are combinations of a) through c) listedimmediately hereinabove.

FIG. 36 shows an array of portable memory units referred to hereinabove,each used for transporting an encryption/decryption key from an implantsite to a remote station, for storing it in the remote station and forencryption/decryption at the time of communication between a remotestation and a particular IMD. The array forms a memory bank in a remotestation communication device, allowing the remote station operator tocommunicate with each of a number of different IMDs. In one preferredembodiment of the invention, the portable memory units are write-onceonly; In another (or the same) preferred embodiment of the invention,these memory units may not be read or duplicated, though they are usedfor encryption/decryption. By not allowing for either duplication or fortransmitting the key, an additional security measure is obtained.

FIG. 37 shows a system with two key generators, one for IMD-Station #1communications, and one for IMD-Station #2 communications. Stations #1and #2 could be any two different stations from which communicate withthe IMD; For example, Station #1 could be a central station formanagement of IMDs and Station #2 could be the IMD owner's physician'soffice. As shown in the figure, the two key generators are freestanding, analogous to FIG. 35A. However, either one of the generators(or both) could be part of the IMD (analogous to FIG. 35B), or eitherone of the generators (or both) could be part of the respective remotestation (analogous to FIG. 35C).

FIG. 38A shows an encryption method which uses a digitized form of anitem of patient data obtained by the IMD during the previous IMD-RemoteStation session in the generation of the key to be used in the currentsession. By so doing, a) the key changes from session to session, and b)only the remote station which participated in the previous session canparticipate in the next session. This approach may be used to change thekey during a session, as well. In FIG. 38A, the key for the next sessionis generated at the IMD and is transmitted to the remote station.

FIG. 38B shows a variation in which, the patient data on which the keyis based is generated at the IMD and is transmitted to the remotestation (rather than the approach of FIG. 38A in which the key itself istransmitted). The patient data is used to generate the key for the nextremote station-IMD communication, using a key generator in the remotestation whose function is identical to that of the key generator withinthe IMD (i.e. for a specific set of patient data, both the remotestation key generator and the IMD key generator will generate a matchingset of encryption/decryption keys).

FIG. 39 shows an example of a digitized electrogram signal. The measuredvoltage is used to generate a series of numbers which can be used togenerate a new encryption/decryption key. The waveform may be sampledmore frequently or less frequently. The data may be digitized on a 16bit scale, a 32 bit scale or with any arbitrary degree of accuracy. Thedigitized data may be transformed in any of a variety of ways, as isknown in the art.

An example of such patient data would be a waveform in a patientelectrogram, or intervals between patient heartbeats, determined by anICD. In the figure, the key generator within the IMD updates both theIMD memory and the memory of the remote station with a new key, eitherat the end of each session, or during a session.

IMD Owner's Permission to Access IMD

During certain scenarios, it may be impractical or undesirable torequire the IMD owner's permission. For example, if the IMD is an ICDwhich is repeatedly shocking the owner for atrial fibrillation, and theowner is physically incapable of granting permission, it would bedesirable to reprogram or inhibit the device without permission.

If, on the other hand, an elective reprogramming of the IMD isdesirable, or if the download of new software is desirable, thepermission of the IMD may be sought. Requiring such permission makes itless likely that an unauthorized person could gain access to the IMD.

FIGS. 40, 41 and 42 show flow diagrams of three possible methods ofpermission granting.

-   -   In FIG. 40, both the instruction/program/command for the IMD and        a patient permission request are sent to an external device such        as the CPD or WD. The external device notifies the patient of a        permission request. The notification may be a telephone message,        a tone indicating that a message is to be retrieved, etc. The        message may state a) the source, b) the content/purpose of the        instruction/program/command, c) a contact person/phone number        that the IMD owner may communicate with to receive additional        information, the level of urgency of the requested download        (e.g. low urgency for software update; high urgency for        arrhythmia in progress). If the IMD owner grants permission        (e.g. by pressing a key or sequence of keys on the CPD), the IMD        instruction is downloaded from the CPD or WD to the IMD and is        installed/enacted. Three options are listed in the figure in the        event of either a) no response, or b) a negative response.    -   In the approach shown in FIG. 41: a) the instruction is sent to        a buffer or labile memory of the IMD and b) permission to        install/enact is sent to the IMD owner via the WD or CPD. If the        owner grants permission, he so indicates via the WD or CPD,        which signals the IMD to install/enact the instruction stored in        its buffer/labile memory. If permission is not granted, three        options are listed in the figure including the possibility of        deleting the instruction from the buffer/labile memory.    -   In the approach shown in FIG. 42, the initial action by the        person desiring to issue an IMD instruction is only to send a        permission request to the IMD owner. If permission is granted,        then the IMD instruction is sent to the IMD, and confirmation of        installation or of enacting the instruction is sent back to the        CS or MD who sent the instruction.

Formats for outside access to an IMD in relationship to IMD ownerpermission include:

1) Under all circumstances, no outside access without IMD-ownerpermission;

2) IMD access without requesting permission in the event of anemergency, emergency defined in advance, and IMD owner, in advance,grants emergency access rights [to one or more individuals or centers orto all centers or individuals];

3) IMD access without requesting permission if

-   -   (a) emergency in progress;    -   (b) person obtaining access knows one or more passwords and/or        one or more encryption keys; or    -   (c) both (a) and (b)

4) IMD access under all circumstances, if in judgment of medicalprofessional access is warranted.

FIG. 43 shows a block diagram of one type of locator system. The aim ofthe locator system is to establish with a great degree of certaintywhere a patient with an implanted device is located, without using thebattery of the implanted device. The purpose of locating the patient isto optimize communication between a remote station and the device with ahigh degree of certainty, for as great a fraction of the time aspossible. The first locator is either attached to an implanted unit, isimplanted in the patient, unattached to the unit, or is outside of thepatient's body, but designed to be either worn or in reliably closeproximity to the patient.

A first locator unit 4300 contains transmitter 4302 which emits locatorsignals for detection by a receiver 4304 in the second locator unit4306. The presence and quality of the signals from 4302 are evaluated byassessment device 4308, and the assessment may be shared with otherunits in the system. The information may be used for (a) modifying thepath and entities which communicate, (b) modifying the communicationparameters (e.g. power output, sensitivity, signal compression,transmission rate, etc) of one or more of the communicating units, (c)producing an alarm or other means of notifying either a patient, a userof the medical device, a person who can contact the patient or someonein proximity to the patient. The goal is to optimize communicationsbetween the medical device 4310 and the remote station 4312.

FIG. 44 shows a block diagram of a second type of locator system. Thefirst locator in this system 4402 is designed not to require a battery,though it may use a backup one. It derives its energy from thetransmitter 4404 of the second locator unit 4400. The energy is storedin storage device 4406 which may be a capacitor, a battery, or otherenergy storage device as is known in the art. The stored energy is usedto power first locator transmitter 4408. FIGS. 45 and 46 show thearchitecture of a communication system which links a remote station withan electronic medical device via one or more relay units. The relayunits may be stationary or mobile. The system shown in FIGS. 45 and 46uses motion detecting apparatus in one or more of the relay units,electronic medical device and remote station to (a) generate locationinformation for the units (FIG. 45) and to generate communicationoptimization information (FIG. 46).

FIGS. 47 and 48 show another architecture of a communication systemwhich links a remote station with an electronic medical device via oneor more relay units. The relay units may be stationary or mobile. Thesystem shown in FIGS. 47 and 48 uses the analysis of signal strength inone or more of the relay units, electronic medical device and remotestation to generate communication optimization information, based on thestrength and quality of received signals.

System architectures which use both signal strength and the detection ofmotion are possible, and various configurations will be determinable tothose skilled in the art.

FIG. 49 shows a schematic view of the optimization of communicationroute involving communication relay units numbered 1 through z. In oneapproach, parameters related to each of the 0.5(z+1)(z+2) pairs ofpossible communication links (e.g. distance, power output, range, systemuse, and others), may be individually evaluated, or may bemathematically transformed and further evaluated. More complexmathematical transformations involving (a) multiple properties, and (b)multiple pairs of units (or all units) are possible.

There has thus been shown and described novel apparatus and methodologyfor controlling an implantable medical device which fulfills all theobjects and advantages sought therefor. Many changes, modifications,variations and other uses and applications of the subject inventionwill, however, become apparent to those skilled in the art afterconsidering this specification and the accompanying drawings whichdisclose the preferred embodiments thereof. All such changes,modifications, variations and other uses and applications which do notdepart from the spirit and scope of the invention are deemed to becovered by the invention, which is to be limited only by the claimswhich follow.

1. A medical treatment system having an implantable medical device,which allows a person using the device to be easily located, tofacilitate communication between the device and a remote location, saidsystem comprising: (1) electronic medical apparatus adapted to beimplanted in a human, a so-called implantable medical device (IMD)comprising, in combination: (a) a first transmitting/receiving (T/R)device for at least one of (i) transmitting information to, and (ii)receiving at least one control signal from, at least one remotelocation; (b) a medical treatment device, coupled to said first T/Rdevice, for treating said patient in response to control signals appliedthereto; (2) a first locator device, adapted to be located in thevicinity of said human, comprising a wireless first locator transmittingdevice, operative to transmit first locator signals; (3) a secondlocator device, comprising: (a) a second locator receiving device,operative to receive said first locator signals; (b) a communicationquality assessment device, coupled to said second locator receivingdevice, for assessing the quality of the received locator signals, andfor producing a communication quality signal in dependence upon theassessed quality of said first locator signals; and (c) a second locatortransmitting device, coupled to said communication quality assessmentdevice, for transmitting said communication quality signal; (4) acommunication device, comprising (a) a second T/R device, forcommunicating with: (i) the second locator transmitting device, forreceiving said communication quality signal, and (ii) said first T/Rdevice; (b) a second T/R controlling device, coupled to said second T/Rdevice, for controlling the mode of communication of said second T/Rdevice; wherein: (a) said communication quality assessment devicedetermines information concerning the location of said first locatorbased on at least one of: (i) the detection of said first locator signalby said second locator, (ii) the absence of a detected first locatorsignal by said second locator, and (iii) the intensity of said detectedfirst locator signal; (b) said second locator transmits the informationconcerning the location of said first locator to said communicationdevice; and (c) said second T/R controlling device is operative tocontrol a mode of communication between said second T/R device and saidfirst T/R device, in dependence upon said location information; therebyto improve communication with the IMD.
 2. The medical treatment systemdefined in claim 1, wherein said first locator device and said IMD aremechanically linked, such that both are adapted to be implanted in saidhuman in whom both said devices continue to be mechanically linked. 3.The medical treatment system defined in claim 1, wherein said IMD andsaid first locator device are adapted to be implanted in said human, butare not mechanically linked.
 4. The medical treatment system defined inclaim 3, wherein said first locator device is adapted to be implantedsubcutaneously in said human and said IMD is adapted to be implanted ata deeper level than the subcutaneous layer.
 5. The medical treatmentsystem defined in claim 1, wherein said IMD is adapted to be implantedin said human and said first locator device is adapted to be locatedoutside of said human, touching the outer surface of the skin of saidhuman.
 6. The medical treatment system defined in claim 1, wherein saidIMD is adapted to be implanted in said human and said first locatordevice is adapted to be located outside of said human, and is physicallylinked to an article worn by said human.
 7. The medical treatment systemdefined in claim 6, wherein said article of clothing includes at leastone of: a belt, a watch and jewelry.
 8. The medical treatment systemdefined in claim 1, wherein said second T/R controlling device isoperative to control a mode of communication selected from the groupconsisting of: (i) a power output for said second T/R device; (ii) asignal sensitivity for said second T/R device; (iii) at least onetransmission frequency for said second T/R device; (iv) an output signalmodulation type for said second T/R device; (v) a selection of at leastone of a connection via (a) a radiofrequency link, (b) Internet, (c) ahard wire connection, for said second T/R device; (vi) a rate ofinformation transfer by said second T/R device (vii) a method of signalencoding by said second T/R device; (viii) a message repetitionfrequency, for said second T/R device; and (ix) a selection of at leastone other communication device with which said second T/R devicecommunicates.
 9. The medical treatment system defined in claim 1,further comprising (4) alarm apparatus, situated in proximity to atleast one of (i) said person, and (ii) another person, comprising: (a) anotification device for producing at least one output from the groupconsisting of a sound, a light and a vibration; and (b) a receivingdevice, coupled to said notification device, for receiving at least oneof (i) a first locator signal, and (ii) said communication qualitysignal; wherein said receiving device causes said notification device toproduce said at least one output: (i) in the absence of a received firstlocator signal, (ii) upon receipt of a low quality first locator signal,(iii) upon receipt of a communication quality signal indicating anunacceptable quality communication between said first and said secondlocator device; thereby to notify at least one of (i) said person and(ii) said other person that the location of said first locator devicerequires attention.
 10. The medical treatment system defined in claim 1,wherein said second locator device further comprises a notificationdevice, coupled to said communication quality assessment device, forproducing at least one output from the group consisting of: a sound, alight and a vibration; and wherein at least one of: (i) the absence of areceived first locator signal; (ii) the receipt of an unacceptablequality first locator signal; causes the production of said at least oneoutput by said notification device; thereby to notify at least one of(i) said person and (ii) said other person that the location of saidfirst locator device requires attention.
 11. The medical treatmentsystem defined in claim 1, wherein the IMD includes at least one sensor,coupled to said first T/R device for sensing a medical condition of saidperson and producing a sensor output signal in response to said medicalcondition, wherein said first T/R device transmits a representation ofsaid sensor output signal.
 12. The medical treatment system defined inclaim 11, wherein said sensor is further coupled to said medicaltreatment device and wherein said medical treatment device automaticallyapplies an appropriate treatment to said patient in response thereto.13. The medical treatment system defined in claim 1, wherein saidcommunication device is located at said remote location and furthercomprises: (c) a first input device, coupled to said second T/R device,responsive to a technical expert, for producing at least one real timeremote control signal for controlling said EMD unit.
 14. The medicaltreatment system defined in claim 1, further comprising a remote station(RS) at said remote location including: (a) a first input device,responsive to a medical expert, for producing at least one real timeremote control signal for controlling said EMD unit; and (b) a thirdtransmitting/receiving (T/R) device, coupled to said input device, forelectronic communication with at least one of (i) the first T/R deviceof said remotely located IMD, and (ii) the second T/R device of saidcommunication device.
 15. The medical treatment system defined in claim14, wherein: (a) said second T/R device is operative to re-transmit saidreceived communication quality signal to said third T/R device; and (b)said remote station further comprises a third T/R controlling device,coupled to said third T/R device, for controlling the mode ofcommunication between said third T/R device and at least one of saidfirst T/R device and said second T/R device; thereby to permit saidthird T/R device to improve its communications.
 16. The medicaltreatment system defined in claim 14, wherein said technical expert isoperative to notify at least one of: (a) said person; (b) another personin the vicinity of said person; of a received communication qualitysignal indicating an unacceptable quality communication between saidfirst and said second locator device.
 17. The medical treatment systemdefined in claim 16 further comprising: (4) alarm apparatus, situated inproximity to at least one of (i) said person, and (ii) another person,comprising: (a) a notification device for producing at least one of asound, a light and a vibration; and (b) a receiving device, coupled tosaid notification device; wherein said technical expert sends an alarmsignal to said first input device, for transmission by said third T/Rdevice to said alarm apparatus; thereby to notify at least one of (i)said person, and (ii) another person, of said unacceptable qualitycommunication.
 18. The medical treatment system defined in claim 1,wherein: (a) said second T/R device is operative to re-transmit saidreceived communication quality signal to said first T/R device; and (b)said IMD further comprises a first T/R controlling device, coupled tosaid first T/R device, for controlling the mode of communication betweensaid first T/R device and said second T/R device; thereby to cause saidfirst T/R device to improve its communications with said second T/Rdevice.
 19. The medical treatment system defined in claim 17, wherein:(a) said second T/R device is operative to re-transmit said receivedcommunication quality signal to said first T/R device; and (b) said IMDfurther comprises a first T/R controlling device, coupled to said firstT/R device, for controlling the mode of communication between said firstT/R device and at least one of said second T/R device and said third T/Rdevice; thereby to permit said first T/R device to improve itscommunications with at least one of said second T/R device and saidthird T/R device.
 20. The medical treatment system defined in claim 1,wherein: (a) said second locator device further comprises an additionaltransmitting device, for transmitting a first assessment signal, (b)said first locator device further comprises a first locator receivingdevice, coupled to said first locator transmitting device, for receivingsaid first assessment signal, and (c) said first locator transmittingdevice is further operative to transmit a second assessment signal; (d)said communication quality assessment device is operative to assess thequality the received second assessment signal, and for producing saidcommunication quality signal in dependence upon the assessed quality ofsaid second assessment signal; wherein (i) said second locator devicetransmits said first assessment signal to said first locator device;(ii) upon receipt of said first assessment signal, said first locatordevice transmits a second assessment signal to said second locatordevice; and (iii) said communication quality assessment device assessessaid second assessment signal; thereby to assess the quality ofcommunication between the two locator devices.
 21. A medical treatmentsystem having an implantable medical device, which allows a person usingthe device to be easily located, to facilitate communication between thedevice and a remote location, said system comprising: (1) electronicmedical apparatus adapted to be implanted in a human, a so-calledimplantable medical device (IMD) comprising, in combination: (a) a firsttransmitting/receiving (T/R) device for at least one of (i) transmittinginformation to, and (ii) receiving at least one control signal from, atleast one remote location; (b) a medical treatment device, coupled tosaid first T/R device, for treating said patient in response to controlsignals applied thereto; (2) a first locator device, adapted to be inthe vicinity of said human, comprising: (a) a first locator receivingdevice; (b) an energy storage device, coupled to said first locatorreceiving device, for storing energy contained in incoming electricalsignals; (c) a first locator transmitting device, coupled to said energystorage device and to said first locator receiving device, operative totransmit first locator signals; (3) a second locator device, comprising:(a) a second locator transmitting device, operative to transmit secondlocator signals, for receipt by said first locator receiving device; (b)a second locator receiving device, operative to receive said firstlocator signals; (c) a communication quality assessment device, coupledto said second locator receiving device, for assessing the quality ofsaid received first locator signals, and for producing a communicationquality signal in dependence upon the assessed quality of said firstlocator signals; and (d) a second locator quality signal transmittingdevice, coupled to said communication quality assessment device, fortransmitting said communication quality signal; (4) a communicationdevice, comprising (a) a second T/R device, for communicating with: (i)the second locator transmitting device, for receiving said communicationquality signal, and (ii) said first T/R device; (b) a second T/Rcontrolling device, coupled to said second T/R device, for controllingthe mode of communication of said second T/R device; wherein: (a) saidtransmitted second locator signals, received by said first locatorreceiver, supply energy for powering said first locator device; (b) saidcommunication quality assessment device determines informationconcerning the location of said first locator based on at least one of:(i) the detection of said first locator signal by said second locator,(ii) the absence of a detected first locator signal by said secondlocator, and (iii) the intensity of said detected first locator signal;(c) said second locator transmits the information concerning thelocation of said first locator to said communication device; and (d)said second T/R controlling device is operative to control a mode ofcommunication between said second T/R device and said first T/R device,in dependence upon said location information; thereby to improvecommunication with the IMD.
 22. The medical treatment system defined inclaim 21, wherein said first locator device and said IMD aremechanically linked, such that both are adapted to be implanted in saidhuman in whom both said devices continue to be mechanically linked. 23.The medical treatment system defined in claim 21, wherein said IMD andsaid first locator device are adapted to be implanted in said human, butare not mechanically linked.
 24. The medical treatment system defined inclaim 23, wherein said first locator device is adapted to be implantedsubcutaneously in said human and said IMD is adapted to be implanted ata deeper level than the subcutaneous layer.
 25. The medical treatmentsystem defined in claim 21, wherein said IMD is adapted to be implantedin said human and said first locator device is adapted to be locatedoutside of said human, touching the outer surface of the skin of saidhuman.
 26. The medical treatment system defined in claim 21, whereinsaid IMD is adapted to be implanted in said human and said first locatordevice is adapted to be located outside of said human, and is physicallylinked to an article worn by said human.
 27. The medical treatmentsystem defined in claim 26, wherein said article of clothing includes atleast one of: a belt, a watch and jewelry.
 28. The medical treatmentsystem defined in claim 21, wherein said second T/R controlling deviceis operative to control a mode of communication selected from the groupconsisting of: (i) a power output for said second T/R device; (ii) asignal sensitivity for said second T/R device; (iii) at least onetransmission frequency for said second T/R device; (iv) an output signalmodulation type for said second T/R device; (v) a selection of at leastone of a connection via (a) a radiofrequency link, (b) Internet, (c) ahard wire connection, for said second T/R device; (vi) a rate ofinformation transfer by said second T/R device (vii) a method of signalencoding by said second T/R device; (viii) a message repetitionfrequency, for said second T/R device; and (ix) a selection of at leastone other communication device with which said second T/R devicecommunicates.
 29. The medical treatment system defined in claim 21,further comprising: (4) alarm apparatus, situated in proximity to atleast one of (i) said person, and (ii) another person, comprising: (a) anotification device for producing at least one output from the groupconsisting of a sound, a light and a vibration; and (b) a receivingdevice, coupled to said notification device, for receiving at least oneof (i) a first locator signal, and (ii) said communication qualitysignal; wherein said receiving device causes said notification device toproduce said at least one output: (i) in the absence of a received firstlocator signal, (ii) upon receipt of a low quality first locator signal,(iii) upon receipt of a communication quality signal indicating anunacceptable quality communication between said first and said secondlocator device; thereby to notify at least one of (i) said person and(ii) said other person that the location of said first locator devicerequires attention.
 30. The medical treatment system defined in claim21, wherein said second locator device further comprises a notificationdevice, coupled to said communication quality assessment device, forproducing at least one output from the group consisting of: a sound, alight and a vibration; and wherein at least one of: (i) the absence of areceived first locator signal; (ii) the receipt of an unacceptablequality first locator signal; causes the production of said at least oneoutput by said notification device; thereby to notify at least one of(i) said person and (ii) said other person that the location of saidfirst locator device requires attention.
 31. The medical treatmentsystem defined in claim 21, wherein the IMD includes at least onesensor, coupled to said first T/R device for sensing a medical conditionof said person and producing a sensor output signal in response to saidmedical condition, wherein said first T/R device transmits arepresentation of said sensor output signal.
 32. The medical treatmentsystem defined in claim 31, wherein said sensor is further coupled tosaid medical treatment device and wherein said medical treatment deviceautomatically applies an appropriate treatment to said patient inresponse thereto.
 33. The medical treatment system defined in claim 21,wherein said communication system is located at said remote location andfurther comprises: (c) a first input device, coupled to said second T/Rdevice, responsive to a technical expert, for producing at least onereal time remote control signal for controlling said EMD unit.
 34. Themedical treatment system defined in claim 21, further comprising aremote station (RS) at said remote location including: (a) a first inputdevice, responsive to a medical expert, for producing at least one realtime remote control signal for controlling said EMD unit; (b) a thirdtransmitting/receiving (T/R) device, coupled to said input device, forelectronic communication with at least one of (i) the first T/R deviceof said remotely located IMD, and (ii) the second T/R device of saidcommunication device.
 35. The medical treatment system defined in claim34, wherein: (a) said second T/R device is operative to re-transmit saidreceived communication quality signal to said third T/R device; and (b)said remote station further comprises a third T/R controlling device,coupled to said third T/R device, for controlling the mode ofcommunication between said third T/R device and at least one of saidfirst T/R device and said second T/R device; thereby to permit saidthird T/R device to improve its communications.
 36. The medicaltreatment system defined in claim 34, wherein said technical expert isoperative to notify at least one of: (a) said person; (b) another personin the vicinity of said person; of a received communication qualitysignal indicating an unacceptable quality communication between saidfirst and said second locator device.
 37. The medical treatment systemdefined in claim 36 further comprising: (4) alarm apparatus, situated inproximity to at least one of (i) said person, and (ii) another person,comprising: (a) a notification device for producing at least one of asound, a light and a vibration; and (b) a receiving device, coupled tosaid notification device; wherein said technical expert sends an alarmsignal to said first input device, for transmission by said third T/Rdevice to said alarm apparatus; thereby to notify at least one of (i)said person, and (ii) another person, of said unacceptable qualitycommunication.
 38. The medical treatment system defined in claim 21,wherein: (a) said second T/R device is operative to re-transmit saidreceived communication quality signal to said first T/R device; and (b)said IMD further comprises a first T/R controlling device, coupled tosaid first T/R device, for controlling the mode of communication betweensaid first T/R device and said second T/R device; thereby to permit saidfirst T/R device to improve its communications with said second T/Rdevice.
 39. The medical treatment system defined in claim 37, wherein:(a) said second T/R device is operative to re-transmit said receivedcommunication quality signal to said first T/R device; and (b) said IMDfurther comprises a first T/R controlling device, coupled to said firstT/R device, for controlling the mode of communication between said firstT/R device and at least one of said second T/R device and said third T/Rdevice; thereby to permit said first T/R device to improve itscommunications with at least one of said second T/R device and saidthird T/R device.
 40. The medical treatment system defined in claim 21,wherein: (a) said first locator device further comprises a first locatorcommunication quality assessment device, coupled to said first locatorreceiving device and to said first locator transmitting device, forassessing the quality of the received second locator signals and forproducing a first locator communication quality signal in dependenceupon the assessed quality of said second locator signals; (b) said firstlocator transmitting device is operative to transmit said first locatorcommunication quality signal to said second locator device; (c) saidsecond locator device further comprises a second locator transmittingdevice controller, coupled to said second locator receiving device, forreceipt of said first locator communication quality signal, and coupledto at least one of: (I) said second locator transmitting device, forcontrolling at least one of: (i) the power output of said second locatortransmitting device; (ii) the transmitter frequency of said secondlocator transmitting device; (iii) the repetition rate of said secondlocator transmitting device; and (iv) the direction of transmission ofsaid second locator transmitting device; and (II) said second locatorquality signal transmitting device, to control a mode of communicationselected from the group consisting of: (i) a power output for saidsecond locator transmitting device; (ii) at least one transmissionfrequency for said second locator transmitting device; (iii) an outputsignal modulation type for said second locator transmitting device; (iv)a selection of at least one of a connection via (a) a radiofrequencylink, (b) Internet, (c) a hard wire connection, for said second locatortransmitting device; (v) a rate of information transfer by said secondlocator transmitting device; (vi) a method of signal encoding by saidsecond locator transmitting device; (vii) a message repetitionfrequency, for said second locator transmitting device; and (viii) aselection of at least one other communication device with which saidsecond locator transmitting device communicates. thereby to improvecommunication between said second locator device and at least one ofsaid first locator device and another device.
 41. The medical treatmentsystem defined in claim 21, wherein: (a) said first locator devicefurther comprises a first locator communication quality assessmentdevice coupled to said first locator receiving device and to said firstlocator transmitting device for assessing the quality of the receivedsecond locator signals, and for producing a first locator communicationquality signal, in dependence upon the assessed quality of said secondlocator signals; (b) said first locator transmitting device is operativeto transmit said first locator communication quality signal to saidsecond locator device; (c) said second locator receiving device isfurther coupled to said second locator transmitting device, tore-transmit said first locator communication quality signal; (d) saidsecond T/R device is operative to receive said re-transmitted firstlocator communication quality signal; and (e) said second T/Rcontrolling device is operative to control a mode of communicationbetween said second T/R device and said first T/R device, in dependenceupon said first locator communication quality signal; thereby to improvecommunication to said IMD.
 42. The medical treatment system defined inclaim 41, wherein: (a) said second T/R device is operative tore-transmit said received first locator communication quality signal;(b) said first T/R device is operative to receive said re-transmittedfirst locator communication quality signal; (c) said IMD furthercomprises a first T/R controlling device, coupled to said first T/Rdevice, for controlling the mode of communication between said first T/Rdevice and said second T/R device; thereby to cause said first T/Rdevice to improve communication with said second T/R device.
 43. Themedical treatment system defined in claim 41, further comprising aremote station (RS) at said remote location comprising: (a) a firstinput device, responsive to a technical expert, for producing at leastone real time remote control signal for controlling said IMD; (b) athird transmitting/receiving (T/R) device, coupled to said input device,for electronic communication with at least one of (i) the first T/Rdevice of said remotely located IMD, and (ii) the second T/R device ofsaid communication device; (c) a third T/R controlling device, coupledto said third T/R device, for controlling the mode of communicationbetween said third T/R device and at least one of said first T/R deviceand said second T/R device; and (d) said second T/R device is operativeto re-transmit said received first locator communication quality signal;wherein: (i) said third T/R device receives said re-transmitted firstlocator communication quality signal; and (ii) said third T/Rcontrolling device controls the mode of communication of said third T/Rdevice based on said first locator communication quality signal; therebyto cause said third T/R device to improve its communications.
 44. Amedical treatment system having a medical device which allows a personusing the device access to a medical expert that can communicate withthe medical device from a remote site, said system comprising, incombination: (A) an electronic medical device (EMD) unit comprising, incombination: (1) a first wireless transmitting/receiving (T/R) devicefor transmitting information to, and for receiving at least one controlsignal from, a plurality of remote locations; (2) a medical treatmentdevice, coupled to said first T/R device, for treating said person inresponse to control signals applied thereto; (B) a remote station (RS)unit at said remote location including: (1) a first input device,responsive to a medical expert, for producing at least one real timeremote control signal for controlling said EMD; (2) a secondtransmitting/receiving (T/R) device, coupled to said input device, forelectronic communication with the first T/R device of said remotelylocated EMD; and (C) at least one communication relay unit, x saidcommunication relay unit(s) numbered from “1” to “x”, each ythcommunication relay unit including a (y+2)th communication relaytransmitting/receiving (T/R) device for communicating with at least twoof (i) the EMD, (ii) the RS, (iii) one of said communication relayunits, and (iv) at least one other communication relay unit, wherein (1)x is an integer which is at least the integer 1 (2) y is an integerranging from the integer 1 to the integer x; and wherein at least one ofsaid units is a first unit further comprising: (a) a first globalpositioning system, for determining a location of said first unit; (b) afirst communication quality assessment device, coupled to said firstglobal positioning system, for assessing the expected quality ofcommunication signals to be received by the T/R device associated withat least one of (i) said first unit and (ii) at least one other of saidunits, and for producing a first communication quality signal independence upon the respective expected quality of said communicationsignals; and (b) a first mode selection device coupled to saidrespective, associated T/R device and said first communication qualityassessment device for selecting the mode of communication with at leastone other one of said units, in response to receipt of saidcommunication quality signal from said communication quality assessmentdevice; thereby to select a mode of communication in dependence upon thecurrent location of said unit and to improve the communication of saidEMD unit and said RS unit;
 45. The medical treatment system defined inclaim 44, wherein said EMD unit includes at least one sensor, coupled tosaid first T/R device for sensing a medical condition of said person andproducing a sensor output signal in response to said medical condition,wherein said first T/R device transmits a representation of said sensoroutput signal to at least one of (i) at least one of said xcommunication relay units, and (ii) said RS unit.
 46. The medicaltreatment system defined in claim 45, wherein said sensor is furthercoupled to said medical treatment device and wherein said medicaltreatment device is operative to automatically apply an appropriatetreatment to said patient in response thereto.
 47. The medical treatmentsystem defined in claim 44, wherein the EMD unit is adapted to beimplanted in said person.
 48. The medical treatment system defined inclaim 44, wherein, upon the detection of a location, a respective modeselection device of said at least one first unit is operative to controlat least one of: (i) the selection of at least one other unit with whichsaid at least one first unit communicates; (ii) a power output for saidT/R device of said first unit; (iii) a signal sensitivity for said T/Rdevice of said first unit; (iv) at least one transmission frequency forsaid T/R device of said first unit; (v) an output signal modulation typefor said T/R device of said first unit; (vi) a selection of at least oneof a connection via (a) a radiofrequency link, (b) Internet, (c) a hardwire connection, for said T/R device of said first unit; (vii) a rate ofinformation transfer; (viii) a method of signal encoding; and (ix) amessage repetition frequency.
 49. The medical treatment system definedin claim 44, wherein: (a) the respective communication qualityassessment device includes a memory for storing a location of at leastone stationary communication unit selected from the group consisting of(i) a stationary remote station, and (ii) at least one stationarycommunication relay unit; and (b) said global positioning system isoperative to repeatedly determine the spatial relationship between saidat least one first unit and at least one of (i) said stationary remotestation and (ii) said at least one stationary communication relay unit.50. The medical treatment system defined in claim 44, wherein: (1) theglobal positioning system of said at least one first unit is coupled tothe respective T/R device of said at least one first unit, fortransmission of respective labeled coordinate information including: (a)information which identifies said respective first unit; and (b)location information relating to said respective first unit; (2) an atleast one other second unit includes: (a) a respective secondcommunication quality assessment device, coupled to the respective T/Rdevice of said second unit, for receipt of said labeled coordinateinformation from said at least one first unit, and for producing arespective second communication quality signal in dependence upon saidlabeled coordinate information; and (b) a second mode selection devicecoupled to said respective T/R device of said second unit and to saidsecond communication quality assessment device, for selecting the modeof communication between at least one pair of units, each said paircomprising (i) said second unit and (ii) a first unit, in response toreceipt of said respective second communication quality signal from saidsecond communication quality assessment device; whereby said secondcommunication quality assessment device is responsive to said locationinformation from said at least one first unit, to determine if said atleast one pair of units is in an acceptable location for communication.51. The medical treatment system defined in claim 50, wherein (a) saidat least one second unit further comprises a second global positioningsystem, coupled to said second communication quality assessment device,for determining a location of said second unit; (b) said at least onesecond communication assessment device is operative to utilize locationinformation from each pair of units wherein one member of the pair isselected from said at least one first unit and the other member of thepair is selected from said at least one second unit, to determine atleast one of: (i) a change in the position of each of the two members ofeach pair of two units; (ii) the presence of a motionless state of apair, in which neither member of such pair of said units is moving, and(iii) the presence of a state in which at least one member of a pair ofsaid units is moving.
 52. The medical treatment system defined in claim51, wherein (a) at least one of said second units is a local controlunit; (b) at least two of said first units transmit respective labeledcoordinate information to said at least one local control unit; (c) thecommunication quality assessment device of said local control unit isoperative to analyze all received location information and to determineoptimization information comprising at least one of (i) an optimal routefor communications among said second unit and said at least two firstunits, and (ii) optimal communication parameters for said second unitand said at least two first units; (d) the communication qualityassessment device of said local control unit is further coupled to theT/R device of said local control unit, to cause said T/R device totransmit said optimization information, for each first which transmittedsaid respective labeled coordinate information; and (e) the T/R deviceof each of said first units is coupled to the respective communicationquality assessment device of said first units; wherein (i) each of saidfirst units transmits respective labeled coordinate information to saidlocal control unit; (ii) the communication quality assessment device ofsaid local control unit determines respective optimization informationfor said first units; (iii) said optimization information is transmittedto said first units, and supplied to said respective mode selectiondevice of said first units; thereby to improve communication among saidlocal control unit and said at least two first units.
 53. The medicaltreatment system defined in claim 51, comprising one second unit and aplurality of first units, wherein, (a) each of a plurality of firstunits transmits respective labeled coordinate information to said onesecond unit; (b) the communication quality assessment device of saidsecond unit is operative to analyze all received location informationand determine optimization information comprising at least one of (i) aroute for improved communication among said second unit and saidplurality of first units, and (ii) parameters for improved communicationamong said second unit and said plurality of first units; (c) thecommunication quality assessment device of said second unit is furthercoupled to the T/R device of said second unit, to cause said device totransmit said optimization information; and (d) the T/R device of eachof said plurality of first units is coupled to the respectivecommunication quality assessment device of each of said first unit;wherein (i) each of said plurality of first units transmits respectivelabeled coordinate information to said second unit; (ii) thecommunication quality assessment device of said second unit determinessaid optimization information for said second unit and said plurality offirst units; (iii) said optimization information is transmitted to saidfirst units, and passed to each said respective mode selection device;whereby said second unit is a master control unit; thereby to optimizecommunications between said EMD unit and said RS unit.
 54. The medicaltreatment system defined in claim 53, wherein: (a) the communicationquality assessment device of said master control unit includes a memoryfor storing a location of all stationary units; and (b) saidcommunication quality assessment device of said master control unit isoperative to determine the spatial relationship between each saidstationary unit, and each other unit.
 55. The medical treatment devicesystem defined in claim 52, wherein said communication parametersinclude at least one of: (i) a choice of power output for at least oneT/R device; (ii) a choice of signal sensitivity for at least one T/Runit; (iii) a choice of at transmission frequency for at least one T/Runit; (iv) a choice of output signal modulation type for at least oneT/R unit; (v) a choice of the rate of information transfer; (vi) achoice of the method of signal encoding; and (vii) a choice of messagerepetition frequency.
 56. The medical treatment device system defined inclaim 53, wherein said communication parameters include at least one of:(i) a choice of power output for at least one T/R device; (ii) a choiceof signal sensitivity for at least one T/R unit; (iii) a choice of attransmission frequency for at least one T/R unit; (iv) a choice ofoutput signal modulation type for at least one T/R unit; (v) a choice ofthe rate of information transfer; (vi) a choice of the method of signalencoding; and (vii) a choice of message repetition frequency.
 57. Themedical treatment system defined in claim 51, wherein: (a) the T/Rdevice of at least one additional unit is operative to (i) receive saidlabeled coordinate information from said at least one first unit, and(ii) re-transmit said information; (b) the T/R device of said at leastone second unit is operative to receive said re-transmitted labeledcoordinate information; and (c) the mode selection device of said atleast one second unit is operative to select the mode of communicationbetween: (1) said at least one second unit and (2) at least one of: (i)said at least one first unit, which initially transmitted saidcoordinate information, (ii) said at least one additional, whichre-transmitted said coordinate information, and (iii) yet one otherunit; thereby to allow position information of a unit to be propagatedamong the medical treatment system units, to optimize communicationswithin the medical treatment system.
 58. The medical treatment systemdefined in claim 52, wherein: (a) the T/R device of at least one moreunit is operative to (i) receive said optimization information from saidat least one second unit, and (ii) re-transmit said optimizationinformation; (b) the T/R device of said at least one first unit isoperative to receive said re-transmitted optimization information; and(c) the selection device of said at least one first unit is operative toselect the mode of communication between (1) said at least one firstunit and (2) at least one of: (i) said at least one second unit, whichinitially transmitted said optimization information, (ii) said at leastone more unit, which re-transmitted said optimization information, and(iii) yet one other unit; thereby to allow communication optimizationinformation to be propagated among the medical treatment system units,to optimize communications within the medical treatment system.
 59. Themedical treatment system defined in claim 44, wherein at least one ofsaid at least one first units further comprises a respective velocitydetermination device, coupled to said respective first globalpositioning system and to said respective first communication qualityassessment device, for determining at least one of (i) the average speedof said respective first unit, over an interval of time, and (ii) thenet direction of motion of said respective first unit, over saidinterval of time; wherein, said respective velocity determination devicecalculates at least one of said respective average speed, and (ii) saidrespective net direction by comparing (i) a respective position of saidrespective first unit at a first instant in time, with a respectiveposition of said respective first unit at a second instant in time. 60.The medical treatment system defined in claim 59, wherein (1) thevelocity determining device of said at least one first unit is coupledto the respective T/R device of said at least one first unit, fortransmission of respective labeled velocity information including: (a)information which identifies said respective first unit; (b) arespective time of said first instant and of said second instant; and(c) velocity information relating to said respective first unit,including at least one of:  (i) said average speed during said intervalof time; and  (ii) said net direction of motion; (2) an at least oneother second unit includes: (a) a respective second communicationquality assessment device, coupled to the respective T/R device of saidsecond unit, for receipt of said labeled velocity information from saidat least one first unit, and for producing a respective secondcommunication quality signal in dependence upon said labeled velocityinformation; and (b) a second mode selection device coupled to saidrespective T/R device of said second unit and to said secondcommunication quality assessment device, for selecting the mode ofcommunication between at least one pair of units, each said paircomprising: (i) said second unit and (ii) a first unit, in response toreceipt of said respective second communication quality signal from saidsecond communication quality assessment device; whereby said secondcommunication quality assessment device is responsive to said velocityinformation from said at least one first unit, to determine if said atleast one pair of units will be in an acceptable location forcommunication, at a future instant in time.
 61. The medical treatmentsystem defined in claim 60, wherein (a) said at least one second unitfurther comprises a second velocity determining device, coupled to saidsecond communication quality assessment device, for determining at leastone of (i) an average speed and (ii) a net direction of said secondunit; (b) said at least one second communication assessment device isoperative to utilize velocity information from each pair of unitswherein one member of the pair is selected from said at least one firstunit and the other member of the pair is selected from said at least onesecond unit, to determine at least one of: (i) a change in the at leastone of the average speed and the net direction of each of the twomembers of each pair of two units; (ii) the relative average speed andthe relative net direction of each pair of the two members; and (iii)the presence of a motionless state of a pair, in which neither member ofsuch pair of said units is moving.
 62. The medical treatment systemdefined in claim 44, wherein at least one of said at least one firstunits further comprises a respective velocity determination device whichis operative to determine at least one of (i) the magnitude of anacceleration of said respective first unit, over an interval of time,and (ii) the net direction of acceleration of said respective firstunit, over said interval of time; wherein, said respective velocitydetermination device calculates at least one of (i) the magnitude ofsaid respective acceleration, and (ii) said respective net direction ofsaid acceleration by comparing a respective average speed and netdirection of motion of said respective first unit at a first instant intime, with a respective average speed and net direction of motion ofsaid respective first unit at a second instant in time.
 63. The medicaltreatment system defined in claim 62 further comprising a device fordetermining when the value of said magnitude of said respectiveacceleration exceeds a threshold, to determine a likelihood of at leastone of (i) a collapse of said person, and (ii) a collision of a movingvehicle containing said person.
 64. A medical treatment system having amedical device which allows a person using the device access to amedical expert that can communicate with the medical device from aremote site, said system comprising, in combination: (1) an electronicmedical device (EMD) unit comprising, in combination: (a) a firstwireless transmitting/receiving (T/R) device for transmittinginformation to, and for receiving at least one control signal from, aplurality of remote locations; (b) a medical treatment device, coupledto said first T/R device, for treating said person in response tocontrol signals applied thereto; (2) a remote station (RS) unit at saidremote location including: (a) a first input device, responsive to amedical expert, for producing at least one real time remote controlsignal for controlling said EMD unit; (b) a secondtransmitting/receiving (T/R) device, coupled to said input device, forelectronic communication with the first T/R device of said remotelylocated EMD unit; and (3) at least one communication relay unit, x saidunit(s) numbered from “1” to “x”, each yth unit including: (a) a (y+2)thcommunication relay transmitting/receiving (T/R) device forcommunicating with at least two of (i) the EMD unit, (ii) the RS unit,(iii) one of said communication relay units, and (iv) at least one othercommunication relay unit; (b) a yth communication quality assessmentdevice for assessing at least one of the expected and the actual qualityof communications signals to be received by said (y+2)th communicationrelay T/R device from at least one of (i) said EMD unit, (ii) said RSunit, and (iii) said at least one other communication relay unit, andfor producing a yth communication quality signal in dependence upon therespective assessed quality of the communication signals; and (c) a ythmode selection device coupled to each of said respective (y+2)th T/Rdevice and said respective communication quality assessment device forselecting the mode of communication with at least one of (i) said EMDunit, (ii) said RS unit, and (iii) said at least one other communicationrelay unit, in response to receipt of said respective communicationsquality signal from said respective communication quality assessmentdevice; wherein (1) x is an integer which is at least the integer 1, and(2) y is an integer ranging from the integer 1 to the integer x; wherebycommunication between said EMD and said RS may be improved.
 65. Themedical treatment system defined in claim 64, wherein said RS furthercomprises: (a) an RS communication quality assessment device forassessing at least one of the expected and the actual quality ofcommunications signals to be received by said second T/R device from atleast one of (i) said EMD unit, and (ii) said at least one communicationrelay unit, and for producing a RS communication quality signal independence upon the respective assessed quality of the communicationsignals; and (b) an RS mode selection device coupled to said second T/Rdevice and said RS communication quality assessment device for selectingthe mode of communication with at least one of (i) said EMD unit, and(ii) said at least one other communication relay unit, in response toreceipt of said RS communications quality signal from said RScommunication quality assessment device; whereby communication betweenthe RS and at least one other unit may be improved.
 66. The medicaltreatment system defined in claim 64, wherein said EMD furthercomprises: (a) an EMD communication quality assessment device forassessing at least one of the expected and the actual quality ofcommunications signals to be received by said first T/R device from atleast one of (i) said RS unit, and (ii) said at least one communicationrelay unit, and for producing an EMD communication quality signal independence upon the respective assessed quality of the communicationsignals; and (b) an EMD mode selection device coupled to said first T/Rdevice and said EMD communication quality assessment device forselecting the mode of communication with at least one of (i) said RSunit, and (ii) said at least one other communication relay unit, inresponse to receipt of said EMD communications quality signal from saidEMD communication quality assessment device; whereby communicationbetween the EMD and at least one other unit may be improved.
 67. Themedical treatment system defined in claim 64, wherein said communicationquality assessment device is coupled to said (y+2)th T/R device andmeasures the quality of communication signals actually received by the(y+2)th T/R device.
 68. The medical treatment system defined in claim65, wherein said RS communication quality assessment device is coupledto said second T/R device and measures the quality of communicationsignals actually received by the second T/R device.
 69. The medicaltreatment system defined in claim 66, wherein said EMD communicationquality assessment device is coupled to said first T/R device andmeasures the quality of communication signals actually received by thefirst T/R device.
 70. The medical treatment system defined in claim 64,wherein said yth communication quality assessment device assesses theexpected quality of communication signals to be received by the (y+2)thT/R device, based upon at least one external factor.
 71. The medicaltreatment system defined in claim 65, wherein said RS communicationquality assessment device assesses the expected quality of communicationsignals to be received by the second T/R device, based upon at least oneexternal factor.
 72. The medical treatment system defined in claim 66,wherein said EMD communication quality assessment device assesses theexpected quality of communication signals to be received by the firstT/R device, based upon at least one external factor.
 73. The medicaltreatment system defined in claim 70, wherein said at least one externalfactor is selected from the group consisting of: (a) a previousassessment of expected quality, (b) a distance to another communicationrelay unit, (c) a state of motion of said communication relay unit, (d)atmospheric conditions, (e) a time of the day, and (f) a day of theyear.
 74. The medical treatment system defined in claim 71, wherein saidat least one external factor is selected from the group consisting of:(a) a previous assessment of expected quality, (b) a distance to atleast one of: (i) at least one communication relay unit, and (ii) saidEMD unit, (c) a state of motion of said RS unit, (d) atmosphericconditions, (e) a time of the day, and (f) a day of the year.
 75. Themedical treatment system defined in claim 72, wherein said at least oneexternal factor is selected from the group consisting of: (a) a previousassessment of expected quality, (b) a distance to at least one of: (i)at least one communication relay unit, and (ii) said RS unit, (c) astate of motion of said EMD unit, (d) atmospheric conditions, (e) a timeof the day, and (f) a day of the year.
 76. The medical treatment systemdefined in claim 64, wherein the EMD unit includes at least one sensor,coupled to said first T/R device for sensing a medical condition of saidperson and producing a sensor output signal in response to said medicalcondition, wherein said first T/R device transmits a representation ofsaid sensor output signal to at least one of said x communication relayunits.
 77. The medical treatment system defined in claim 76, whereinsaid sensor is further coupled to said medical treatment device andwherein said medical treatment device automatically applies anappropriate treatment to said patient in response thereto.
 78. Themedical treatment system defined in claim 64, wherein the EMD unit isadapted to be implanted in said patient.
 79. The medical treatmentsystem defined in claim 67, wherein: (a) at least one of (i) a testcommunication relay unit, including a respective test communicationrelay transmitting/receiving (T/R) device for communicating with atleast two of (i) the EMD unit, (ii) the RS unit, (iii) one of saidcommunication relay units, and (iv) at least one other communicationrelay unit, (ii) said RS unit, and (iii) said EMD unit, includes adevice for generating a test signal which identifies the respective unitwhich has transmitted said test signal, said device coupled to therespective T/R device of said at least one unit; (c) the signal qualityassessment device of at least one other communication relay unit isoperative to produce a test signal quality signal, indicating thequality of the test signal received by said at least one othercommunication relay unit; and (d) the selection device of said at leastone other communication relay unit is operative to select the mode ofcommunication between (1) said at least one other communication relayunit and (2) at least one of: (i) the unit which transmitted said testsignal, (ii) at least one other unit, in response to receipt of therespective test signal quality signal from said respective signalquality assessment device; thereby to improve the quality of thecommunications between the unit which transmitted said test signal andthe communications relay unit which received said test signal to renderacceptable communications within the medical treatment system.
 80. Themedical treatment system defined in claim 68, wherein: (a) at least oneof (i) a test communication relay unit, including a respective testcommunication relay transmitting/receiving (T/R) device forcommunicating with at least two of (i) the EMD unit, (ii) the RS unit,(iii) one of said communication relay units, and (iv) at least one othercommunication relay unit, and (ii) said EMD unit includes a device forgenerating a test signal which identifies the respective unit which hastransmitted said test signal, said device coupled to the respective T/Rdevice of said at least one unit; (b) said RS further comprises (i) asignal quality assessment device operative to produce a RS test signalquality signal, indicating the quality of the test signal received bysaid RS unit, coupled to said second T/R; and (ii) a selection device,coupled to said RS signal quality assessment device and said second T/Rdevice, operative to select the mode of communication between (1) saidRS unit and (2) at least one of: (i) the unit which transmitted saidtest signal, (ii) at least one other unit, in response to receipt ofsaid RS test signal quality signal from said RS signal qualityassessment device; thereby to improve the quality of the communicationsbetween the unit which transmitted said test signal and said RS unit torender acceptable communications within the medical treatment system.81. The medical treatment system defined in claim 69, wherein: (a) atleast one of (i) a test communication relay unit, including a respectivetest communication relay transmitting/receiving (T/R) device forcommunicating with at least two of (i) the EMD unit, (ii) the RS unit,(iii) one of said communication relay units, and (iv) at least one othercommunication relay unit, and (ii) said RS unit, includes a device forgenerating a test signal which identifies the respective unit which hastransmitted said test signal, said device coupled to the respective T/Rdevice of said at least one unit; (b) said EMD further comprises (i) asignal quality assessment device operative to produce an EMD test signalquality signal, indicating the quality of the test signal received bysaid EMD unit, coupled to said second T/R; and (ii) a selection device,coupled to said EMD signal quality assessment device and said first T/Rdevice, operative to select the mode of communication between (1) saidEMD unit and (2) at least one of: (i) the unit which transmitted saidtest signal, (ii) at least one other unit, in response to receipt ofsaid EMD test signal quality signal from said EMD signal qualityassessment device; thereby to improve the quality of the communicationsbetween the unit which transmitted said test signal and said EMD unit torender acceptable communications within the medical treatment system.82. The medical treatment system defined in claim 67, wherein: (a) atleast one of said at least one communication relay unit, a testcommunication relay unit, includes a device for generating a test signalwhich identifies the respective unit which has transmitted said testsignal, said device coupled to the respective T/R device of said atleast one communication relay unit; (b) the signal quality assessmentdevice of at least one other communication relay unit is operative toproduce a test quality signal, representing the quality of the testsignal received by said at least one other communication relay unit; and(c) the mode selection device of said at least one other communicationrelay unit is operative to: (A) select the mode of communication between(1) said at least one other communication relay unit and (2) at leastone of: (i) the unit which transmitted said test signal, and (ii) atleast one other unit; and (B) cause said T/R device of said at least oneother communication relay unit to transmit a mode selection command tosaid respective test communication relay unit; (d) the mode selectiondevice of said respective test communication relay unit is furthercoupled to said respective test communication relay T/R device, toreceive said mode selection command, and in response thereto, to selectthe mode of communication between (1) said respective test communicationrelay unit and (2) at least one of: (i) said respective othercommunication relay unit and (ii) at least one other unit; thereby tocause said respective other communication relay unit to control the modeof communication of at least another communication relay unit.
 83. Themedical treatment system defined in claim 64, wherein at least onecommunication relay unit includes at least one motion detecting device,coupled to said respective communication quality assessment device;thereby to determine if a communication relay unit is in an acceptablelocation or state of motion.
 84. The medical treatment system defined inclaim 83, wherein said at least one motion detecting device is selectedfrom the group consisting of (i) an accelerometer-based motion detector,(ii) a piezoelectric crystal-based motion detector, and (iii) a globalpositioning system-based motion detector.
 85. The medical treatmentsystem defined in claim 83, wherein, upon the detection of anon-acceptable location or state of motion, a respective mode selectiondevice of said at least one communication relay unit is operative tocontrol at least one of: (i) the selection of at least one othercommunication relay unit with which said at least one communicationrelay unit communicates; (ii) a power output for said respective (y+2)thT/R unit; (iii) a signal sensitivity for said respective (y+2)th T/Runit; (iv) at least one transmission frequency for said respective(y+2)th T/R unit; (v) an output signal modulation type for saidrespective (y+2)th T/R unit; (vi) a selection of at least one of aconnection via (a) a radiofrequency link, (b) Internet, (c) a hard wireconnection, for said respective (y+2)th T/R unit; (vii) a rate ofinformation transfer; (viii) a method of signal encoding; and (ix) amessage repetition frequency.
 86. The medical treatment system definedin claim 64, wherein: (1) at least one first communication relay unitincludes at least one motion detecting device selected from the groupconsisting of: (i) an accelerometer-based motion detector, (ii) apiezoelectric crystal-based motion detector, and (iii) a globalpositioning system-based motion detector, coupled to the respective(y+2)th T/R device of said at least one first relay unit, fortransmission of labeled coordinate information including: (a)information which identifies said at least one other relay unit; and (b)at least one of location and motion information relating to said atleast one other relay unit; (2) at least one second relay unitcommunication quality assessment device is coupled to said respective(y+2)th T/R device, for receipt of said labeled coordinate informationfrom said at least one first communication relay unit; and (3) said atleast one second relay unit communication quality assessment device isresponsive to at least one of said location and motion information fromsaid at least one first relay unit, to determine if a communicationsrelay unit may be in a sub-optimal location or state of motion.
 87. Themedical treatment system defined in claim 83, wherein (1) at least oneother communication relay includes at least one motion detecting deviceselected from the group: (i) an accelerometer-based motion detector,(ii) a piezoelectric crystal-based motion detector, and (iii) a globalpositioning system-based motion detector, coupled to the respective(y+2)th T/R device of said at least one other relay unit, fortransmission of labeled coordinate information including: (a)information which identifies said at least one other relay unit; and (b)at least one of location and motion information concerning said at leastone other relay unit, and (2) said at least one communication relay unitcommunication quality assessment device is coupled to said respective(y+2)th T/R device, for receipt of said labeled coordinate informationfrom said at least one other relay unit; (3) said at least onecommunication relay unit communications assessment device is responsiveto at least one of said location and motion information from each pairof relay units to determine at least one of: (a) the presence of amotionless state of a pair, in which neither member of a pair of saidrelay units is moving, and (b) the presence of a state in which at leastone member of a pair of said two relay units is moving; wherein onemember of the pair is selected from said at least one relay unit and theother member of the pair is selected from said at least one other relayunit.
 88. The medical treatment system defined in claim 87, wherein, (a)at least one of said at least one communication relay units is a localcontrol unit; (b) at least two of said other relay unit transmitsrespective labeled coordinate information to said at least one localcontrol unit; (c) the communications assessment device of said localcontrol unit is operative to analyze all received motion and locationinformation and determine optimization information comprising at leastone of (i) an optimal route for communications among said local controlunit and said at least two other communication relay units, and (ii)optimal communication parameters for said local control unit and said atleast two other communication relay units, (d) the communicationsassessment device of said local control unit is further coupled to theT/R device of said local control unit, to cause said respective T/Rdevice to transmit said optimization information, for each othercommunications relay unit which transmitted said respective labeledcoordinate information; and (e) the T/R device of each of said othercommunication relay units is coupled to the respective communicationsassessment device of said other communication relays; wherein (iv) eachof said other communication relay units transmits respective labeledcoordinate information to said local control unit; (v) the communicationquality assessment device of said local control unit determinesrespective optimization information for said other communication relayunits; (vi) said optimization information is transmitted to said othercommunication relay units, and supplied to said respective modeselection device of said other communication relay units; thereby toimprove communications among said local control unit and said at leasttwo other communication relay units.
 89. The medical treatment systemdefined in claim 87, wherein, (a) each of a plurality of said othercommunication relay units transmit respective labeled coordinateinformation to a single one of said communication relay units; (b) thecommunication quality assessment device of said single communicationrelay unit is operative to analyze all received motion and locationinformation and determine optimization information comprising at leastone of (i) a route for improved communications among said singlecommunications relay unit and said plurality of other communicationrelay units, and (ii) parameters for improved communication among saidsingle communications relay unit and said plurality of othercommunication relay units; (c) the communication quality assessmentdevice of said single communication relay unit is further coupled to therespective T/R device of said single communication relay unit, to causesaid respective T/R device to transmit said optimization information;and (d) the T/R device of each of said plurality of other communicationrelays is coupled to the respective communications assessment device ofeach of said other communication relays; wherein (iv) each of saidplurality of other communication relay units transmits respectivelabeled coordinate information to said single communication relay unit;(v) the communication quality assessment device of said singlecommunication relay unit determines said optimization information forsaid single communication relay unit and said plurality of othercommunication relay units; (vi) said optimization information istransmitted to said plurality of other communication relay units, andpassed to each said respective mode selection device; whereby saidsingle communication relay unit is a master control unit; thereby tooptimize communications between said EMD unit and said RS unit.
 90. Themedical treatment system defined in claim 89, wherein: (a) thecommunication quality assessment device of said master control unitincludes a memory for storing a location of all stationary communicationrelay units; (b) said motion detecting device of said master controlunit and each of said other communication relay units is a globalpositioning system; and (c) said communication quality assessment deviceof said master control unit is operative to determine a spatialrelationship between each said stationary unit, and each other unit. 91.The medical treatment device system defined in claim 88, wherein saidcommunication parameters include at least one of: (i) a choice of poweroutput for at least one (y+2)th T/R device; (ii) a choice of signalsensitivity for at least one (y+2)th T/R unit; (iii) a choice of attransmission frequency for at least one (y+2)th T/R unit; (iv) a choiceof output signal modulation type for at least one (y+2)th T/R unit; (v)a choice of the rate of information transfer; (vi) a choice of themethod of signal encoding; and (vii) a choice of message repetitionfrequency.
 92. The medical treatment device system defined in claim 89,wherein said communication parameters include at least one of: (i) achoice of power output for at least one (y+2)th T/R device; (ii) achoice of signal sensitivity for at least one (y+2)th T/R unit; (iii) achoice of at transmission frequency for at least one (y+2)th T/R unit;(iv) a choice of output signal modulation type for at least one (y+2)thT/R unit; (v) a choice of the rate of information transfer; (vi) achoice of the method of signal encoding; and (vii) a choice of messagerepetition frequency.
 93. The medical treatment system defined in claim87, wherein: (a) the T/R device of at least one additional communicationrelay device is operative to (i) receive said labeled coordinateinformation from said at least one other relay unit, and (ii)re-transmit said information; (b) the T/R device of said at least onecommunication relay unit is operative to receive said re-transmittedlabeled coordinate information; and (c) the selection device of said atleast one communication relay unit is operative to select the mode ofcommunication between: (1) said at least one communication relay unitand (2) at least one of: (i) said at least one other communication relayunit, which initially transmitted said coordinate information, (ii) saidat least one additional communication relay unit, which re-transmittedsaid coordinate information, (iii) yet one other communication relayunit, (iv) said RS unit, and (v) said EMD unit; thereby to allow atleast one of position and motion information of a communicating unit tobe propagated among the medical treatment system units, to optimizecommunications within the medical treatment system.
 94. The medicaltreatment system defined in claim 88, wherein: (a) the T/R device of atleast one more communication relay device is operative to (i) receivesaid optimization information from said at least one relay unit, and(ii) re-transmit said optimization information; (b) the T/R device ofsaid at least one other communication relay unit is operative to receivesaid re-transmitted optimization information; and (c) the selectiondevice of said at least one other communication relay unit is operativeto select the mode of communication between (1) said at least one othercommunication relay unit and (2) at least one of: (i) said at least onecommunication relay unit, which initially transmitted said optimizationinformation, (ii) said at least one more communication relay unit, whichre-transmitted said optimization information, (iii) yet one othercommunication relay unit, (iv) said RS unit, and (v) said EMD unit;thereby to allow communication optimization information to be propagatedamong the medical treatment system units, to optimize communicationswithin the medical treatment system.
 95. The medical treatment systemdefined in claim 90, wherein said determination of an optimal route ofcommunications includes the determination of a communications pathbetween said EMD unit and said RS unit, via z said communication relayunits, wherein at least one of: (a) the largest value of all of thedistances between each of ½(z+2)(z+1) possible pairs of communicatingunits which are included in said route is minimized; (b) the largestvalue of each of ½(z+2)(z+1) first mathematical functions of at leastone of (i) the distance between a pair of communicating units and (ii)the maximum communication range of one member of the pair, and (iii) themaximum range of the other member of the pair, (iv) the maximumsensitivity of one member of the pair and (v) the maximum sensitivity ofthe other member of the pair, is minimized; (c) the smallest value ofeach of a ½(z+2)(z+1) second mathematical functions of at least one of(i) the distance between a pair of communicating units and (ii) themaximum communication range of one member of the pair, and (iii) themaximum range of the other member of the pair, (iv) the maximumsensitivity of one member of the pair and (v) the maximum sensitivity ofthe other member of the pair, is maximized. thereby to select a routewherein the weakest link is the most robust possible.
 96. The medicaltreatment system defined in claim 90, wherein said determination of anoptimal route of communications entails the determination of acommunications path between said EMD unit and said RS unit, via z saidcommunication relay units, wherein at least one of: (a) the largestvalue of a third function of all of the distances between each of½(z+2)(z+1) possible pairs of communicating units which are included insaid route is minimized; (b) the smallest value of a third function ofall of the distances between each of ½(z+2)(z+1) possible pairs ofcommunicating units which are included in said route is maximized.thereby to select a maximally robust route.
 97. The medical treatmentsystem defined in claim 67, wherein (1) at least one other communicationrelay unit includes a signal quality assessment device, coupled to therespective T/R device of said other communication relay unit, operativeto produce an incoming quality signal, representing the quality of thecommunication signals received by said respective T/R device; (2) saidsignal quality assessment device of said at least one othercommunication relay unit is further coupled to the said T/R device ofsaid at least one other relay unit, for transmission of labeled signalquality information, representing said respective incoming qualitysignal, including: (a) the identity of said at least one other relayunit; and (b) signal quality information concerning the signals receivedby the respective T/R device of said at least one other relay unit, and(3) said at least one communication relay unit communication qualityassessment device is coupled to said respective T/R device, for (i)receipt of said labeled signal quality information from said at leastone other relay unit, and (ii) assessment of the quality of signalsreceived by said one communication relay unit; (4) said at least onecommunication relay unit communications assessment device is responsiveto at least one of (i) said received labeled signal quality information,and (ii) said assessment of the quality of signals received by said onecommunications relay unit to produce said respective communicationquality signal; whereby the mode selection device of said at least onecommunication relay unit improves the communication between said atleast one communication relay unit and each other communication relayunit from which it receives said labeled signal quality information. 98.The medical treatment system defined in claim 97, wherein, (a) at leastone of said at least one communication relay units is a local controlunit; (b) at least two of said other communication relay units transmitrespective labeled signal quality information to said at least one localcontrol unit; (c) the communication quality assessment device of saidlocal control unit is operative to analyze all received signal qualityinformation and determine optimization information comprising at leastone of (i) an optimal route for communications among said local controlunit and said at least two other communication relay units, and (ii)optimal communication parameters for said local control unit and said atleast two other communication relay units, (d) the communication qualityassessment device of said local control unit is further coupled to theT/R device of said local control unit, to cause said respective T/Rdevice to transmit said optimization information, for each othercommunications relay unit which transmitted said respective labeledsignal quality information; and (e) the T/R device of each of said othercommunication relay units is coupled to the respective communicationquality assessment device of said other communication relays; wherein(i) each of said other communication relay units transmits respectivelabeled signal quality information to said local control unit; (ii) thecommunication quality assessment device of said local control unitdetermines respective optimization information for said othercommunication relay units; (iii) said optimization information istransmitted to said other communication relay units, and supplied tosaid respective mode selection device of said other communication relayunits; thereby to improve communications among said local control unitand said at least two other communication relay units.
 99. The medicaltreatment system defined in claim 97, wherein, (a) each of a pluralityof said other communication relay units transmit respective labeledsignal quality information to a single one of said communication relayunits; (b) the communication quality assessment device of said singlecommunication relay unit is operative to analyze all received signalquality information and determine optimization information comprising atleast one of (i) a route for improved communications among said singlecommunications relay unit and said plurality of other communicationrelay units, and (ii) parameters for improved communication among saidsingle communications relay unit and said plurality of othercommunication relay units; (c) the communication quality assessmentdevice of said single communication relay unit is further coupled to therespective T/R device of said single communication relay unit, to causesaid respective T/R device to transmit said optimization information;and (d) the T/R device of each of said plurality of other communicationrelays is coupled to the respective communications assessment device ofeach of said other communication relays; wherein (i) each of saidplurality of other communication relay units transmits respectivelabeled signal quality information to said single communication relayunit; (ii) the communication quality assessment device of said singlecommunication relay unit determines said optimization information forsaid single communication relay unit and said plurality of othercommunication relay units; (iii) said optimization information istransmitted to said plurality of other communication relay units, andpassed to each said respective mode selection device; whereby saidsingle communication relay unit is a master control unit; thereby tooptimize communications between said EMD unit and said RS unit.
 100. Themedical treatment system defined in claim 99, wherein: (a) thecommunication quality assessment device of said master control unitincludes a memory for storing a location of each stationarycommunication relay units; and (b) said communication quality assessmentdevice of said master control unit is operative to determine the spatialrelationship between each said stationary unit, and each other unit.101. The medical treatment device system defined in claim 98, whereinsaid communication parameters include at least one of: (i) a choice ofpower output for at least one (y+2)th T/R device; (ii) a choice ofsignal sensitivity for at least one (y+2)th T/R unit; (iii) a choice ofat transmission frequency for at least one (y+2)th T/R unit; (iv) achoice of output signal modulation type for at least one (y+2)th T/Runit; (v) a choice of the rate of information transfer; (vi) a choice ofthe method of signal encoding; and (vii) a choice of message repetitionfrequency.
 102. The medical treatment device system defined in claim 99,wherein said communication parameters include at least one of: (i) achoice of power output for at least one (y+2)th T/R device; (ii) achoice of signal sensitivity for at least one (y+2)th T/R unit; (iii) achoice of at transmission frequency for at least one (y+2)th T/R unit;(iv) a choice of output signal modulation type for at least one (y+2)thT/R unit; (v) a choice of the rate of information transfer; (vi) achoice of the method of signal encoding; and (vii) a choice of messagerepetition frequency.
 103. The medical treatment system defined in claim97, wherein: (a) the T/R device of at least one additional communicationrelay device is operative to (i) receive said labeled signal qualityinformation from said at least one other relay unit, and (ii)re-transmit said information; (b) the T/R device of said at least onecommunication relay unit is operative to receive said re-transmittedlabeled signal quality information; and (c) the selection device of saidat least one communication relay unit is operative to select the mode ofcommunication between: (1) said at least one communication relay unitand (2) at least one of: (i) said at least one other communication relayunit, which initially transmitted said signal quality information, (ii)said at least one additional communication relay unit, whichre-transmitted said signal quality information, (iii) yet one othercommunication relay unit, (iv) said RS unit, and (v) said EMD unit;thereby to allow said signal quality information of a communicating unitto be propagated among the medical treatment system units, to optimizecommunications within the medical treatment system.
 104. The medicaltreatment system defined in claim 98, wherein: (a) the T/R device of atleast one more communication relay device is operative to (i) receivesaid optimization information from said at least one relay unit, and(ii) re-transmit said optimization information; (b) the T/R device ofsaid at least one other communication relay unit is operative to receivesaid re-transmitted optimization information; and (c) the selectiondevice of said at least one other communication relay unit is operativeto select the mode of communication between (1) said at least one othercommunication relay unit and (2) at least one of: (i) said at least onecommunication relay unit, which initially transmitted said optimizationinformation, (ii) said at least one more communication relay unit, whichre-transmitted said optimization information, (iii) yet one othercommunication relay unit, (iv) said RS unit, and (v) said EMD unit;thereby to allow communication optimization information to be propagatedamong the medical treatment system units, to optimize communicationswithin the medical treatment system.
 105. A medical treatment andtesting apparatus, for medical treatment of a person, which allows aremote station to perform testing on the apparatus from a remotelocation, said apparatus comprising, in combination: (A) an electronicmedical device comprising, in combination: (1) first transmitting andreceiving device (T/R) device; for transmitting information to, and forreceiving at least one control signal from and a remote station; (2) atleast one sensor for producing a sensor signal representing aphysiologic state of a person; (3) a first processor, having an inputand an output, for receiving said sensor signals, for making a decisionrelated to medical therapy for said person, responsive to said sensorsignals, and for producing a first therapy signal output representingsaid decision; (4) a medical treatment device, for applying medicaltreatment to said person; (5) an input switching device, having: (a) aplurality of inputs, including: (i) one input coupled to said first T/Rdevice, for receipt of test signals, and (ii) at least one other inputcoupled to said at least one sensor, for receipt of sensor signals; (b)an output, coupled to said first processor input; said input switchingdevice being responsive to a first control signal received from saidfirst T/R device for selecting the input to be outputted; (6) an outputswitching device, having: (a) an input, coupled to said first processoroutput for receipt of said first processor therapy signal; (b) aplurality of outputs, including: (i) one output coupled to said medicaltreatment device; and (ii) one output coupled to said first T/R device,for transmission of test results; and said output switching device beingresponsive to a second control signal received from said first T/Rdevice for selecting the output of said output switching device; (B) aremote station unit at said remote location, including: (1) a firstinput device, responsive to a technical expert, for producing at leastone remote control signal for controlling and testing said medicaldevice; (2) a second transmitting/receiving (T/R) device, coupled tosaid input device, for electronic communication with the first T/Rdevice of said remotely located EMD unit; and (3) a first output device,coupled to said second T/R device, for receipt of said first therapysignal; wherein (I) In a first operating state, said input switchingdevice: couples said sensor signal to said first processor input, anduncouples said first T/R device from said first processor input; andsaid output switching device: couples said first processor output tosaid medical treatment device; and uncouples said first processor outputfrom said first T/R device; and (II) In a second operating state, saidinput switching device: uncouples said sensor signal from said firstprocessor input, and couples said first T/R device to said firstprocessor input; and said output switching device: uncouples said firstprocessor output from said medical treatment device; and couples saidfirst processor output to said first T/R device; and (III) saidtechnical expert determines the choice of operating state by inputtingcontrol signals to said second T/R device which are transmitted to saidfirst T/R device, and then passed to the input of each of said inputswitching device and said output switching device, for respectivecontrol thereof; (IV) said technical expert (a) applies test signals tosaid first input device, which are passed sequentially by said secondT/R, said first T/R and said input switching device to said firstprocessor input; and (b) receives the first processor output, which ispassed sequentially by said output switching device, said first T/Rdevice, and said second T/R device, for evaluation; whereby, in saidfirst operating state, said medical treatment device is operative toprovide treatment based on said sensor signals; and in said secondoperating state, said technical expert evaluates the response of saidfirst processor to a test signal, thereby to determine whether saidfirst processor is functioning properly.
 106. The medical treatment andtesting apparatus defined in claim 105, wherein: (a) said remote stationfurther comprises a display device, coupled to said second T/R device,for displaying output information from said first processor, received bysaid second T/R device; and (b) said technical expert is a human;thereby to allow a human technical expert to determine if said firstprocessor is functioning properly in said second operating state. 107.The medical treatment and testing apparatus defined in claim 105,wherein said technical expert is a logic device operative to initiatesaid testing and to determine if said first processor is functioningproperly in said second operating state.
 108. The medical treatment andtesting apparatus defined in claim 105, wherein: (a) said electronicmedical device further comprises a test signal generating device forgenerating at least one test signal, with an output coupled to anotherone of said plurality of inputs of said input switching device; and (b)in a third operating state: said input switching device: uncouples saidsensor signal from said first processor input, uncouples said first T/Rdevice to said first processor input, and couples said test signalgenerating device to said first processor input; and said outputswitching device: uncouples said first processor output from saidmedical treatment device; and couples said first processor output tosaid first T/R device; whereby said technical expert selects said thirdoperating state to determine if said first processor is functioningproperly in said third operating state.
 109. The medical treatment andtesting apparatus defined in claim 108, wherein: (a) said test signalgenerating device is further coupled to said first T/R device; and (b)said technical expert controls said test signal generating device byinputting said at least one test signal generating device control signalinto said first input device; thereby to activate said test signalgenerating device only during said third operating state.
 110. Themedical treatment and testing apparatus defined in claim 108, whereinsaid test signal generating device is further coupled to said first T/Rdevice to cause the transmission by said first T/R device of said atleast one test signal; thereby to cause said at least one test signal tobe received by said second T/R device for evaluation by said technicalexpert to determine if said first processor is functioning properly.111. The medical treatment and testing apparatus defined in claim 105,wherein, in a fourth operating state: said input switching device:couples said sensor signal to said first processor input, and uncouplessaid first T/R device from said first processor input; and said outputswitching device: couples said first processor output to said medicaltreatment device and to said first T/R device; whereby said technicalexpert may evaluate the response of said first processor to said sensorsignals.
 112. The medical treatment and testing apparatus defined inclaim 105, wherein said electronic medical device is adapted to beimplanted in a living being.
 113. The medical treatment and testingapparatus defined in claim 105, wherein said electronic medical deviceis adapted to be attached outside the body of a living being.
 114. Themedical treatment and testing apparatus defined in claim 105, wherein(a) said first processor is further coupled to said first T/R device;and (b) said technical expert includes means for providing aninstruction to said first input device for transmission to said firstT/R device, said instruction comprising at least one of a command, acomplete program, a part of a program, a complete operating system, anda part of an operating system for said first processor; thereby to allowsaid technical expert to provide said instructions to said firstprocessor.
 115. The medical treatment and testing apparatus defined inclaim 114, wherein: (a) said electronic medical device is operative totransmit a received instruction back to said remote station; and (b)said remote station further comprises a computer device, coupled to eachof said first input device and to said second T/R device, for (i)storing: (I) an instruction transmitted by said remote station, and (II)said received instruction; (ii) comparing the transmitted instructionwith said received instruction; and (iii) generating at least onecomparison signal which indicates whether said transmitted instructionand said received instruction are the same; thereby to conveyinformation to said technical expert indicating whether said transmittedinstruction was properly received by said electronic medical device.116. The medical treatment and testing apparatus defined in claim 105,further comprising a second processor, coupled to each of: (a) said atleast one sensor; (b) said first processor; and (c) said medicaltreatment device; said second processor having an input and an output,for receiving said sensor signals, for making a decision related tomedical therapy for said person, responsive to said sensor signals, andfor producing a second therapy signal output representing said decision;wherein: (i) said first processor is operative to signal said secondprocessor of the operating state; (ii) in said second operating state,said second processor is operative to make a therapy decision for saidperson, in response to said sensor signals, and for producing a secondtherapy signal output representing said decision; (iii) said medicaltreatment device is operative to apply medical treatment to said personin response to said second therapy signal from said second processor;whereby said electronic medical device utilizes said second processor toperform the decision-related functions of said first processor, whilesaid first processor is undergoing evaluation testing, thereby toprovide uninterrupted therapy to said person.
 117. The medical treatmentand testing apparatus defined in claim 116, wherein said secondprocessor is operative to provide information to said first processorrelating to at least one of the sensor signals and the respective secondprocessor decision which occur during the duration of the secondoperating state.
 118. The medical treatment and testing apparatusdefined in claim 116, wherein (a) said first processor is furthercoupled to said first T/R device; (b) said second processor is coupledto said first processor; and wherein (i) said technical expert includesmeans for providing a first instruction to said first input device fortransmission to said first T/R device, said instruction comprising atleast one of a command, a complete program, a part of a program, acomplete operating system, and a part of an operating system for saidfirst processor; and (ii) said technical expert includes means forproviding a second instruction to said first input device fortransmission to said first T/R device, said instruction comprising atleast one of a command, a complete program, and a part of a program, forsaid first processor, causing said first processor to provide a copy ofsaid first instruction to said second processor; thereby to provide saidfirst instruction to both said first and said second processors. 119.The medical treatment and testing apparatus in claim 116, wherein saidsecond processor is coupled to each of: (a) said input switching device;and (b) said output switching device; and wherein, in said secondoperating state, said second processor is operative to cause said inputswitching device and said output switching device to return saidelectronic medical device to said first operating state; thereby toreturn to said first operating state in the event of a physiologicalstate which requires therapy by said first processor.
 120. The medicaltreatment and testing apparatus in claim 119, wherein said firstprocessor produces an availability signal consisting of at least one of(a) a first processor available signal, and (b) a first processorunavailable signal, and provides said availability signal to said secondprocessor, and wherein said second processor does not cause a transitionfrom said second operating state to said first operating state when saidfirst processor is unavailable.
 121. The medical treatment and testingapparatus defined in claim 105, further comprising: (C) at least onecommunication relay unit, x said unit(s) numbered from “1” to “x”, eachyth unit including a (y+2)th communication relay transmitting/receiving(T/R) device for communicating with at least two of (i) said electronicmedical device, (ii) said remote station, (iii) one of saidcommunication relay units, and (iv) at least one other communicationrelay unit, wherein (1) x is an integer which is at least the integer 1,and (2) y is an integer ranging from the integer 1 to the integer x;whereby communication between said electronic medical device and saidremote station may be improved.
 122. The medical treatment and testingapparatus defined in claim 121, wherein (a) said remote station furthercomprises a remote station computer, coupled to each of said first inputdevice and to said second T/R device, for (i) the storage of a firstinstruction transmitted by said remote station; (ii) the storage of asecond instruction received by said remote station; (iii) the comparisonof said transmitted instruction with said received instruction; and (iv)the generation of at least one comparison signal which indicates anydifference between said first instruction and said second instruction;and (b) at least one communication relay unit further comprises arespective communication relay unit memory device, coupled to therespective T/R device of said relay unit, for storage of a receivedfirst instruction, and re-transmission as a second instruction; wherein:(1) said technical expert is operative to provide a first instruction,comprising at least one of a command, a complete program, a part of aprogram, a complete operating system, and a part of an operating systemfor said first processor; (2) said first instruction is received by therespective communication relay T/R unit, and stored in said respectivecommunication relay unit computer as a stored first instruction; (3)said stored first instruction is retransmitted by said respectivecommunication relay T/R unit as a second instruction; (4) said secondinstruction is received by said remote station and stored in said remotestation computer; (5) said remote station computer generates at leastone comparison signal which indicates any difference between said firstinstruction and said second instruction; thereby to inform saidtechnical expert whether said transmitted first instruction was properlyreceived by said communication relay unit.
 123. The medical treatmentand testing apparatus defined in claim 121, wherein at least one of saidcommunication relay units further comprises: (a) a communication qualityassessment device for assessing at least one of the expected and theactual quality of communications signals to be received by saidrespective communication relay T/R device from at least one of (i) saidelectronic medical device, (ii) said remote station, and (iii) said atleast one other communication relay unit, and for producing a respectivecommunication quality signal in dependence upon the respective assessedquality of the communication signals; and (b) a mode selection device,coupled to each of said respective T/R device and said respectivecommunication quality assessment device of said at least onecommunication relay unit, for selecting the mode of communication withat least one of (i) said electronic medical device, (ii) said remotestation, and (iii) said at least one other communication relay unit, inresponse to receipt of said respective communication quality signal fromsaid respective communication quality assessment device; wherebycommunication between said electronic medical device and said remotestation may be improved.